SERVER-49831 Add support for base MatchExpression in grammar

12 files changed, 2424 insertions, 2116 deletions

diff --git a/src/mongo/db/cst/bson_lexer.cpp b/src/mongo/db/cst/bson_lexer.cpp
index 6e8c4088615..a5eaebcd9aa 100644
--- a/src/mongo/db/cst/bson_lexer.cpp
+++ b/src/mongo/db/cst/bson_lexer.cpp
@@ -291,7 +291,27 @@ void BSONLexer::tokenize(BSONElement elem, bool includeFieldName) {
     }
 }
 
-BSONLexer::BSONLexer(std::vector<BSONElement> pipeline) {
+BSONLexer::BSONLexer(BSONObj obj, PipelineParserGen::token_type startingToken) {
+
+    _tokens.emplace_back(startingToken, getNextLoc());
+    _tokens.emplace_back(PipelineParserGen::token::START_OBJECT, getNextLoc());
+    for (auto&& elem : obj) {
+        // Include field names in the object.
+        tokenize(elem, true);
+    }
+    _tokens.emplace_back(PipelineParserGen::token::END_OBJECT, getNextLoc());
+
+    // Final token must indicate EOF.
+    _tokens.emplace_back(PipelineParserGen::make_END_OF_FILE(getNextLoc()));
+
+    // Reset the position to use in yylex().
+    _position = 0;
+};
+
+BSONLexer::BSONLexer(std::vector<BSONElement> pipeline,
+                     PipelineParserGen::token_type startingToken) {
+
+    _tokens.emplace_back(startingToken, getNextLoc());
     _tokens.emplace_back(PipelineParserGen::token::START_ARRAY, getNextLoc());
     for (auto&& elem : pipeline) {
         // Don't include field names for stages of the pipeline (aka indexes of the pipeline array).
diff --git a/src/mongo/db/cst/bson_lexer.h b/src/mongo/db/cst/bson_lexer.h
index e9a602c2cd8..e1e92653d62 100644
--- a/src/mongo/db/cst/bson_lexer.h
+++ b/src/mongo/db/cst/bson_lexer.h
@@ -40,7 +40,8 @@ namespace mongo {
 
 class BSONLexer {
 public:
-    explicit BSONLexer(std::vector<BSONElement> input);
+    BSONLexer(BSONObj obj, PipelineParserGen::token_type startingToken);
+    BSONLexer(std::vector<BSONElement> pipeline, PipelineParserGen::token_type startingToken);
 
     /**
      * Retrieves the next token in the stream.
diff --git a/src/mongo/db/cst/bson_lexer_test.cpp b/src/mongo/db/cst/bson_lexer_test.cpp
index 6a5eb631e68..f2b9c55283e 100644
--- a/src/mongo/db/cst/bson_lexer_test.cpp
+++ b/src/mongo/db/cst/bson_lexer_test.cpp
@@ -50,9 +50,10 @@ void assertTokensMatch(BSONLexer& lexer,
 
 TEST(BSONLexerTest, TokenizesOpaqueUserObjects) {
     auto input = fromjson("{pipeline: [{a: 1, b: '1'}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     assertTokensMatch(lexer,
-                      {PipelineParserGen::token::START_ARRAY,
+                      {PipelineParserGen::token::START_PIPELINE,
+                       PipelineParserGen::token::START_ARRAY,
                        PipelineParserGen::token::START_OBJECT,
                        PipelineParserGen::token::FIELDNAME,
                        PipelineParserGen::token::INT_NON_ZERO,
@@ -64,9 +65,10 @@ TEST(BSONLexerTest, TokenizesOpaqueUserObjects) {
 
 TEST(BSONLexerTest, TokenizesReservedKeywords) {
     auto input = fromjson("{pipeline: [{$_internalInhibitOptimization: {}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     assertTokensMatch(lexer,
-                      {PipelineParserGen::token::START_ARRAY,
+                      {PipelineParserGen::token::START_PIPELINE,
+                       PipelineParserGen::token::START_ARRAY,
                        PipelineParserGen::token::START_OBJECT,
                        PipelineParserGen::token::STAGE_INHIBIT_OPTIMIZATION,
                        PipelineParserGen::token::START_OBJECT,
@@ -77,9 +79,10 @@ TEST(BSONLexerTest, TokenizesReservedKeywords) {
 
 TEST(BSONLexerTest, TokenizesReservedKeywordsAtAnyDepth) {
     auto input = fromjson("{pipeline: [{a: {$_internalInhibitOptimization: {}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     assertTokensMatch(lexer,
-                      {PipelineParserGen::token::START_ARRAY,
+                      {PipelineParserGen::token::START_PIPELINE,
+                       PipelineParserGen::token::START_ARRAY,
                        PipelineParserGen::token::START_OBJECT,
                        PipelineParserGen::token::FIELDNAME,
                        PipelineParserGen::token::START_OBJECT,
@@ -93,8 +96,9 @@ TEST(BSONLexerTest, TokenizesReservedKeywordsAtAnyDepth) {
 
 TEST(BSONLexerTest, MidRuleActionToSortNestedObject) {
     auto input = fromjson("{pipeline: [{pipeline: 1.0, coll: 'test'}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     // Iterate until the first object.
+    ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_PIPELINE);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_ARRAY);
     // Kick the lexer to sort the object, which should move element 'coll' in front of 'pipeline'.
     // Not that this only works because these are reserved keywords recognized by the lexer,
@@ -114,8 +118,9 @@ TEST(BSONLexerTest, MidRuleActionToSortNestedObject) {
 TEST(BSONLexerTest, MidRuleActionToSortDoesNotSortNestedObjects) {
     auto input = fromjson(
         "{pipeline: [{$unionWith: {pipeline: [{$unionWith: 'inner', a: 1.0}], coll: 'outer'}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     // Iterate until we reach the $unionWith object.
+    ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_PIPELINE);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_ARRAY);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_OBJECT);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::STAGE_UNION_WITH);
@@ -145,8 +150,9 @@ TEST(BSONLexerTest, MultipleNestedObjectsAreReorderedCorrectly) {
     auto input = fromjson(
         "{pipeline: [{$unionWith: {pipeline: [{$unionWith: 'inner', a: 1.0}], coll: [{$unionWith: "
         "'innerB', a: 2.0}]}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     // Iterate until we reach the $unionWith object.
+    ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_PIPELINE);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_ARRAY);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_OBJECT);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::STAGE_UNION_WITH);
@@ -184,8 +190,9 @@ TEST(BSONLexerTest, MultiLevelBSONDoesntSortChildren) {
     auto input = fromjson(
         "{pipeline: [{$unionWith: {pipeline: [{$unionWith: {'nested': 1.0, 'apple': 1.0}, a: 1.0}],"
         " coll: 'outer'}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     // Iterate until we reach the $unionWith object.
+    ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_PIPELINE);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_ARRAY);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::START_OBJECT);
     ASSERT_EQ(lexer.getNext().type_get(), PipelineParserGen::token::STAGE_UNION_WITH);
@@ -219,5 +226,13 @@ TEST(BSONLexerTest, MultiLevelBSONDoesntSortChildren) {
     assertTokensMatch(lexer, expected);
 }
 
+TEST(BSONLexerTest, EmptyMatchExpressionsAreLexedCorrectly) {
+    BSONLexer lexer(fromjson("{}"), PipelineParserGen::token::START_MATCH);
+    assertTokensMatch(lexer,
+                      {PipelineParserGen::token::START_MATCH,
+                       PipelineParserGen::token::START_OBJECT,
+                       PipelineParserGen::token::END_OBJECT});
+}
+
 }  // namespace
 }  // namespace mongo
diff --git a/src/mongo/db/cst/cst_expression_test.cpp b/src/mongo/db/cst/cst_expression_test.cpp
index 39a2441fa4f..2c0e399bb73 100755
--- a/src/mongo/db/cst/cst_expression_test.cpp
+++ b/src/mongo/db/cst/cst_expression_test.cpp
@@ -48,7 +48,7 @@ TEST(CstExpressionTest, ParsesProjectWithAnd) {
     auto input = fromjson(

         "{pipeline: [{$project: {_id: 9.10, a: {$and: [4, {$and: [7, 8]}]}, b: {$and: [2, "

         "-3]}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -65,7 +65,7 @@ TEST(CstExpressionTest, ParsesProjectWithOr) {
     CNode output;

     auto input = fromjson(

         "{pipeline: [{$project: {_id: 9.10, a: {$or: [4, {$or: [7, 8]}]}, b: {$or: [2, -3]}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -83,7 +83,7 @@ TEST(CstExpressionTest, ParsesProjectWithNot) {
     auto input = fromjson(

         "{pipeline: [{$project: {_id: 9.10, a: {$not: [4]}, b: {$and: [1.0, {$not: "

         "[true]}]}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -99,7 +99,7 @@ TEST(CstExpressionTest, ParsesComparisonExpressions) {
     auto parseAndTest = [](StringData expr) {

         CNode output;

         auto input = fromjson("{pipeline: [{$project: {_id: {$" + expr + ": [1, 2.5]}}}]}");

-        BSONLexer lexer(input["pipeline"].Array());

+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

         auto parseTree = PipelineParserGen(lexer, &output);

         ASSERT_EQ(0, parseTree.parse());

         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -120,21 +120,21 @@ TEST(CstExpressionTest, FailsToParseInvalidComparisonExpressions) {
         {

             CNode output;

             auto input = fromjson("{pipeline: [{$project: {_id: {$" + expr + ": [1]}}}]}");

-            BSONLexer lexer(input["pipeline"].Array());

+            BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

             auto parseTree = PipelineParserGen(lexer, &output);

             ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);

         }

         {

             CNode output;

             auto input = fromjson("{pipeline: [{$project: {_id: {$" + expr + ": [1, 2, 3]}}}]}");

-            BSONLexer lexer(input["pipeline"].Array());

+            BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

             auto parseTree = PipelineParserGen(lexer, &output);

             ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);

         }

         {

             CNode output;

             auto input = fromjson("{pipeline: [{$project: {_id: {$" + expr + ": 1}}}]}");

-            BSONLexer lexer(input["pipeline"].Array());

+            BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

             auto parseTree = PipelineParserGen(lexer, &output);

             ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);

         }

@@ -149,14 +149,14 @@ TEST(CstExpressionTest, FailsToParseInvalidConvertExpressions) {
     {

         CNode output;

         auto input = fromjson("{pipeline: [{$project: {a: {$convert: {input: 'x', to: true}}}}]}");

-        BSONLexer lexer(input["pipeline"].Array());

+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

         auto parseTree = PipelineParserGen(lexer, &output);

         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);

     }

     {

         CNode output;

         auto input = fromjson("{pipeline: [{$project: {a: {$convert: {input: 'x'}}}}]}");

-        BSONLexer lexer(input["pipeline"].Array());

+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

         auto parseTree = PipelineParserGen(lexer, &output);

         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);

     }

@@ -168,7 +168,7 @@ TEST(CstExpressionTest, ParsesConvertExpressions) {
         "{pipeline: [{$project: {a: {$toBool: 1}, b: {$toDate: 1100000000000}, "

         "c: {$toDecimal: 5}, d: {$toDouble: -2}, e: {$toInt: 1.999999}, "

         "f: {$toLong: 1.999999}, g: {$toObjectId: '$_id'}, h: {$toString: false}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -187,7 +187,7 @@ TEST(CstExpressionTest, ParsesConvertExpressionsNoOptArgs) {
     auto input = fromjson(

         "{pipeline: [{$project: {a: {$convert: {input: 1, to: 'string'}}, "

         "b: {$convert : {input: 'true', to: 'bool'}}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

@@ -207,7 +207,7 @@ TEST(CstExpressionTest, ParsesConvertExpressionsWithOptArgs) {
         "{pipeline: [{$project: {a: {$convert: {input: 1, to: 'string', "

         "onError: 'Could not convert'}}, b : {$convert : {input: "

         "true, to : 'double', onNull : 0}}}}]}");

-    BSONLexer lexer(input["pipeline"].Array());

+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);

     auto parseTree = PipelineParserGen(lexer, &output);

     ASSERT_EQ(0, parseTree.parse());

     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);

diff --git a/src/mongo/db/cst/cst_pipeline_translation.cpp b/src/mongo/db/cst/cst_pipeline_translation.cpp
index eefe6e3782c..9cda8109ecb 100644
--- a/src/mongo/db/cst/cst_pipeline_translation.cpp
+++ b/src/mongo/db/cst/cst_pipeline_translation.cpp
@@ -44,6 +44,7 @@
 #include "mongo/db/exec/inclusion_projection_executor.h"
 #include "mongo/db/pipeline/document_source.h"
 #include "mongo/db/pipeline/document_source_limit.h"
+#include "mongo/db/pipeline/document_source_match.h"
 #include "mongo/db/pipeline/document_source_project.h"
 #include "mongo/db/pipeline/document_source_sample.h"
 #include "mongo/db/pipeline/document_source_skip.h"
@@ -442,13 +443,23 @@ auto translateLimit(const CNode& cst, const boost::intrusive_ptr<ExpressionConte
 }
 
 /**
- * Unwrap a sample stage CNode and produce a DocumentSourceSample.
+ * Unwrap a sample stage CNode and produce a DocumentSourceMatch.
  */
 auto translateSample(const CNode& cst, const boost::intrusive_ptr<ExpressionContext>& expCtx) {
     return DocumentSourceSample::create(expCtx, translateNumToLong(cst.objectChildren()[0].second));
 }
 
 /**
+ * Unwrap a match stage CNode and produce a DocumentSourceSample.
+ */
+auto translateMatch(const CNode& cst, const boost::intrusive_ptr<ExpressionContext>& expCtx) {
+    // TODO SERVER-48790, Implement CST to MatchExpression/Query command translation.
+    // And add corresponding tests in cst_pipeline_translation_test.cpp.
+    auto placeholder = fromjson("{}");
+    return DocumentSourceMatch::create(placeholder, expCtx);
+}
+
+/**
  * Walk an aggregation pipeline stage object CNode and produce a DocumentSource.
  */
 boost::intrusive_ptr<DocumentSource> translateSource(
@@ -456,6 +467,8 @@ boost::intrusive_ptr<DocumentSource> translateSource(
     switch (cst.firstKeyFieldname()) {
         case KeyFieldname::project:
             return translateProject(cst.objectChildren()[0].second, expCtx);
+        case KeyFieldname::match:
+            return translateMatch(cst.objectChildren()[0].second, expCtx);
         case KeyFieldname::skip:
             return translateSkip(cst.objectChildren()[0].second, expCtx);
         case KeyFieldname::limit:
diff --git a/src/mongo/db/cst/cst_pipeline_translation_test.cpp b/src/mongo/db/cst/cst_pipeline_translation_test.cpp
index 097c98000d0..96ac483e2fb 100644
--- a/src/mongo/db/cst/cst_pipeline_translation_test.cpp
+++ b/src/mongo/db/cst/cst_pipeline_translation_test.cpp
@@ -42,6 +42,7 @@
 #include "mongo/db/exec/document_value/value_comparator.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/pipeline/document_source_limit.h"
+#include "mongo/db/pipeline/document_source_match.h"
 #include "mongo/db/pipeline/document_source_sample.h"
 #include "mongo/db/pipeline/document_source_single_document_transformation.h"
 #include "mongo/db/pipeline/document_source_skip.h"
@@ -64,7 +65,7 @@ TEST(CstPipelineTranslationTest, TranslatesEmpty) {
     ASSERT_EQ(0u, sources.size());
 }
 
-TEST(CstPipelineTranslationTest, TranslatesEmptyProject) {
+TEST(CstTest, TranslatesEmptyProject) {
     const auto cst = CNode{CNode::ArrayChildren{
         CNode{CNode::ObjectChildren{{KeyFieldname::project, CNode{CNode::ObjectChildren{}}}}}}};
     auto pipeline = cst_pipeline_translation::translatePipeline(cst, getExpCtx());
diff --git a/src/mongo/db/cst/cst_test.cpp b/src/mongo/db/cst/cst_test.cpp
index 179275ace7d..5f766431c1f 100644
--- a/src/mongo/db/cst/cst_test.cpp
+++ b/src/mongo/db/cst/cst_test.cpp
@@ -66,7 +66,7 @@ TEST(CstTest, BuildsAndPrints) {
 TEST(CstGrammarTest, EmptyPipeline) {
     CNode output;
     auto input = fromjson("{pipeline: []}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     ASSERT_TRUE(stdx::get_if<CNode::ArrayChildren>(&output.payload));
@@ -77,14 +77,14 @@ TEST(CstGrammarTest, InvalidPipelineSpec) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$unknownStage: {}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
@@ -93,7 +93,8 @@ TEST(CstGrammarTest, InvalidPipelineSpec) {
             [] {
                 CNode output;
                 auto input = fromjson("{pipeline: 'not an array'}");
-                BSONLexer lexer(input["pipeline"].Array());
+                BSONLexer lexer(input["pipeline"].Array(),
+                                PipelineParserGen::token::START_PIPELINE);
             }(),
             AssertionException,
             13111);
@@ -104,7 +105,7 @@ TEST(CstGrammarTest, ParsesInternalInhibitOptimization) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$_internalInhibitOptimization: {}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -114,7 +115,7 @@ TEST(CstGrammarTest, ParsesInternalInhibitOptimization) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$_internalInhibitOptimization: 'invalid'}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
@@ -124,7 +125,7 @@ TEST(CstGrammarTest, ParsesUnionWith) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$unionWith: {coll: 'hey', pipeline: 1.0}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -134,7 +135,7 @@ TEST(CstGrammarTest, ParsesUnionWith) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$unionWith: {pipeline: 1.0, coll: 'hey'}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -149,7 +150,7 @@ TEST(CstGrammarTest, ParsesUnionWith) {
 TEST(CstGrammarTest, ParseSkipInt) {
     CNode output;
     auto input = fromjson("{pipeline: [{$skip: 5}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -161,7 +162,7 @@ TEST(CstGrammarTest, ParseSkipInt) {
 TEST(CstGrammarTest, ParseSkipDouble) {
     CNode output;
     auto input = fromjson("{pipeline: [{$skip: 1.5}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -173,7 +174,7 @@ TEST(CstGrammarTest, ParseSkipDouble) {
 TEST(CstGrammarTest, ParseSkipLong) {
     CNode output;
     auto input = fromjson("{pipeline: [{$skip: 8223372036854775807}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -185,7 +186,7 @@ TEST(CstGrammarTest, ParseSkipLong) {
 TEST(CstGrammarTest, InvalidParseSkipObject) {
     CNode output;
     auto input = fromjson("{pipeline: [{$skip: {}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
 }
@@ -193,7 +194,7 @@ TEST(CstGrammarTest, InvalidParseSkipObject) {
 TEST(CstGrammarTest, InvalidParseSkipString) {
     CNode output;
     auto input = fromjson("{pipeline: [{$skip: '5'}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
 }
@@ -201,7 +202,7 @@ TEST(CstGrammarTest, InvalidParseSkipString) {
 TEST(CstGrammarTest, ParsesLimitInt) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: 5}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -213,7 +214,7 @@ TEST(CstGrammarTest, ParsesLimitInt) {
 TEST(CstGrammarTest, ParsesLimitDouble) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: 5.0}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -225,7 +226,7 @@ TEST(CstGrammarTest, ParsesLimitDouble) {
 TEST(CstGrammarTest, ParsesLimitLong) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: 123123123123}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -237,7 +238,7 @@ TEST(CstGrammarTest, ParsesLimitLong) {
 TEST(CstGrammarTest, InvalidParseLimitString) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: \"5\"}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
 }
@@ -245,7 +246,7 @@ TEST(CstGrammarTest, InvalidParseLimitString) {
 TEST(CstGrammarTest, InvalidParseLimitObject) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: {}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
 }
@@ -253,7 +254,7 @@ TEST(CstGrammarTest, InvalidParseLimitObject) {
 TEST(CstGrammarTest, InvalidParseLimitArray) {
     CNode output;
     auto input = fromjson("{pipeline: [{$limit: [2]}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
 }
@@ -263,7 +264,7 @@ TEST(CstGrammarTest, ParsesProject) {
         CNode output;
         auto input =
             fromjson("{pipeline: [{$project: {a: 1.0, b: NumberInt(1), _id: NumberLong(1)}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -277,7 +278,7 @@ TEST(CstGrammarTest, ParsesProject) {
         CNode output;
         auto input =
             fromjson("{pipeline: [{$project: {a: 0.0, b: NumberInt(0), c: NumberLong(0)}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -293,7 +294,7 @@ TEST(CstGrammarTest, ParsesProject) {
             "{pipeline: [{$project: {_id: 9.10, a: {$add: [4, 5, {$add: [6, 7, 8]}]}, b: "
             "{$atan2: "
             "[1.0, {$add: [2, -3]}]}}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -406,7 +407,7 @@ TEST(CstGrammarTest, ParsesSampleWithNumericSizeArgument) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: NumberInt(1)}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -417,7 +418,7 @@ TEST(CstGrammarTest, ParsesSampleWithNumericSizeArgument) {
         // Although negative numbers are not valid, this is enforced at translation time.
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: NumberInt(-1)}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -427,7 +428,7 @@ TEST(CstGrammarTest, ParsesSampleWithNumericSizeArgument) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: NumberLong(5)}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -437,7 +438,7 @@ TEST(CstGrammarTest, ParsesSampleWithNumericSizeArgument) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: 10.0}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -448,7 +449,7 @@ TEST(CstGrammarTest, ParsesSampleWithNumericSizeArgument) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: 0}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_EQ(0, parseTree.parse());
         auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -461,21 +462,21 @@ TEST(CstGrammarTest, InvalidParseSample) {
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: 2}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {notSize: 2}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
     {
         CNode output;
         auto input = fromjson("{pipeline: [{$sample: {size: 'gots ta be a number'}}]}");
-        BSONLexer lexer(input["pipeline"].Array());
+        BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
         auto parseTree = PipelineParserGen(lexer, &output);
         ASSERT_THROWS_CODE(parseTree.parse(), AssertionException, ErrorCodes::FailedToParse);
     }
@@ -632,7 +633,7 @@ TEST(CstTest, BuildsAndPrintsType) {
 TEST(CstGrammarTest, ParsesValidNumberAbs) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$abs: 1}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -644,7 +645,7 @@ TEST(CstGrammarTest, ParsesValidNumberAbs) {
 TEST(CstGrammarTest, ParsesValidCeil) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$ceil: 1.5}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -657,7 +658,7 @@ TEST(CstGrammarTest, ParsesValidCeil) {
 TEST(CstGrammarTest, ParsesValidDivide) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$divide: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -670,7 +671,7 @@ TEST(CstGrammarTest, ParsesValidDivide) {
 TEST(CstGrammarTest, ParsesValidExp) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$exp: 1.5}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -683,7 +684,7 @@ TEST(CstGrammarTest, ParsesValidExp) {
 TEST(CstGrammarTest, ParsesValidFloor) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$floor: 1.5}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -696,7 +697,7 @@ TEST(CstGrammarTest, ParsesValidFloor) {
 TEST(CstGrammarTest, ParsesValidLn) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$ln: [37, 10]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -709,7 +710,7 @@ TEST(CstGrammarTest, ParsesValidLn) {
 TEST(CstGrammarTest, ParsesValidLog) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$log: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -722,7 +723,7 @@ TEST(CstGrammarTest, ParsesValidLog) {
 TEST(CstGrammarTest, ParsesValidLog10) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$log10: 1.5}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -735,7 +736,7 @@ TEST(CstGrammarTest, ParsesValidLog10) {
 TEST(CstGrammarTest, ParsesValidMod) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$mod: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -748,7 +749,7 @@ TEST(CstGrammarTest, ParsesValidMod) {
 TEST(CstGrammarTest, ParsesValidMultiply) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$multiply: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -761,7 +762,7 @@ TEST(CstGrammarTest, ParsesValidMultiply) {
 TEST(CstGrammarTest, ParsesValidPow) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$pow: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -774,13 +775,12 @@ TEST(CstGrammarTest, ParsesValidPow) {
 TEST(CstGrammarTest, ParsesValidRound) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$round: [1.234, 2]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
     ASSERT_EQ(1, stages.size());
     ASSERT(KeyFieldname::project == stages[0].firstKeyFieldname());
-    std::cout << "TEDLOG " << stages[0].toBson().toString() << "\n";
     ASSERT_EQ(stages[0].toBson().toString(),
               "{ project: { val: { round: [ \"<UserDouble 1.234000>\", \"<UserInt 2>\" ] } } }");
 }
@@ -788,7 +788,7 @@ TEST(CstGrammarTest, ParsesValidRound) {
 TEST(CstGrammarTest, ParsesValidSqrt) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$sqrt: 25}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -800,7 +800,7 @@ TEST(CstGrammarTest, ParsesValidSqrt) {
 TEST(CstGrammarTest, ParsesValidSubtract) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$subtract: [10, 5]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -813,7 +813,7 @@ TEST(CstGrammarTest, ParsesValidSubtract) {
 TEST(CstGrammarTest, ParsesValidTrunc) {
     CNode output;
     auto input = fromjson("{pipeline: [{$project: {val: {$trunc: [1.234, 2]}}}]}");
-    BSONLexer lexer(input["pipeline"].Array());
+    BSONLexer lexer(input["pipeline"].Array(), PipelineParserGen::token::START_PIPELINE);
     auto parseTree = PipelineParserGen(lexer, &output);
     ASSERT_EQ(0, parseTree.parse());
     auto stages = stdx::get<CNode::ArrayChildren>(output.payload);
@@ -822,5 +822,30 @@ TEST(CstGrammarTest, ParsesValidTrunc) {
     ASSERT_EQ(stages[0].toBson().toString(),
               "{ project: { val: { trunc: [ \"<UserDouble 1.234000>\", \"<UserInt 2>\" ] } } }");
 }
+
+TEST(CstGrammarTest, ParsesEmptyMatchInFind) {
+    CNode output;
+    auto input = fromjson("{}");
+    BSONLexer lexer(input, PipelineParserGen::token::START_MATCH);
+    auto parseTree = PipelineParserGen(lexer, &output);
+    ASSERT_EQ(0, parseTree.parse());
+    auto stage = output;
+    ASSERT(KeyFieldname::match == stage.firstKeyFieldname());
+    ASSERT_EQ(stage.toBson().toString(), "{ match: {} }");
+}
+
+TEST(CstGrammarTest, ParsesMatchInFind) {
+    CNode output;
+    auto input = fromjson("{a: 1.0, b: NumberInt(1), _id: NumberLong(1)}");
+    BSONLexer lexer(input, PipelineParserGen::token::START_MATCH);
+    auto parseTree = PipelineParserGen(lexer, &output);
+    ASSERT_EQ(0, parseTree.parse());
+    auto stage = output;
+    ASSERT(KeyFieldname::match == stage.firstKeyFieldname());
+    ASSERT_EQ(stage.toBson().toString(),
+              "{ match: { a: \"<UserDouble 1.000000>\", b: \"<UserInt 1>\", id: \"<UserLong "
+              "1>\" } }");
+}
+
 }  // namespace
 }  // namespace mongo
diff --git a/src/mongo/db/cst/key_fieldname.h b/src/mongo/db/cst/key_fieldname.h
index e29ee30cd55..1e2b5f3f25e 100644
--- a/src/mongo/db/cst/key_fieldname.h
+++ b/src/mongo/db/cst/key_fieldname.h
@@ -63,6 +63,7 @@
     ENUMIFY(lte)                 \
     ENUMIFY(ne)                  \
     ENUMIFY(project)             \
+    ENUMIFY(match)               \
     ENUMIFY(inhibitOptimization) \
     ENUMIFY(unionWith)           \
     ENUMIFY(collArg)             \
diff --git a/src/mongo/db/cst/location_gen.h b/src/mongo/db/cst/location_gen.h
index c6549fdadbf..e7873ad89d6 100644
--- a/src/mongo/db/cst/location_gen.h
+++ b/src/mongo/db/cst/location_gen.h
@@ -1,4 +1,4 @@
-// A Bison parser, made by GNU Bison 3.6.3.
+// A Bison parser, made by GNU Bison 3.6.
 
 // Locations for Bison parsers in C++
 
@@ -31,12 +31,12 @@
 // version 2.2 of Bison.
 
 /**
- ** \file location_gen.h
+ ** \file src/mongo/db/cst/location_gen.h
  ** Define the mongo::location class.
  */
 
-#ifndef YY_YY_LOCATION_GEN_H_INCLUDED
-#define YY_YY_LOCATION_GEN_H_INCLUDED
+#ifndef YY_YY_SRC_MONGO_DB_CST_LOCATION_GEN_H_INCLUDED
+#define YY_YY_SRC_MONGO_DB_CST_LOCATION_GEN_H_INCLUDED
 
 #include <iostream>
 #include <string>
@@ -53,9 +53,9 @@
 #endif
 #endif
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 namespace mongo {
-#line 59 "location_gen.h"
+#line 59 "src/mongo/db/cst/location_gen.h"
 
 /// A point in a source file.
 class position {
@@ -260,8 +260,8 @@ std::basic_ostream<YYChar>& operator<<(std::basic_ostream<YYChar>& ostr, const l
     return ostr;
 }
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 }  // namespace mongo
-#line 333 "location_gen.h"
+#line 333 "src/mongo/db/cst/location_gen.h"
 
-#endif  // !YY_YY_LOCATION_GEN_H_INCLUDED
+#endif  // !YY_YY_SRC_MONGO_DB_CST_LOCATION_GEN_H_INCLUDED
diff --git a/src/mongo/db/cst/pipeline_grammar.yy b/src/mongo/db/cst/pipeline_grammar.yy
index d962f7ed835..acfef1c5a33 100644
--- a/src/mongo/db/cst/pipeline_grammar.yy
+++ b/src/mongo/db/cst/pipeline_grammar.yy
@@ -206,16 +206,17 @@
 %token <Decimal128> DECIMAL_NON_ZERO
 %token <UserMinKey> MIN_KEY
 %token <UserMaxKey> MAX_KEY
+%token START_PIPELINE START_MATCH
 
 //
 // Semantic values (aka the C++ types produced by the actions).
 //
 
 // Possible user fieldnames.
-%nterm <CNode::Fieldname> projectionFieldname expressionFieldname stageAsUserFieldname
+%nterm <CNode::Fieldname> projectionFieldname expressionFieldname stageAsUserFieldname filterFieldname
 %nterm <CNode::Fieldname> argAsUserFieldname aggExprAsUserFieldname invariableUserFieldname
 %nterm <CNode::Fieldname> idAsUserFieldname valueFieldname
-%nterm <std::pair<CNode::Fieldname, CNode>> projectField expressionField valueField
+%nterm <std::pair<CNode::Fieldname, CNode>> projectField expressionField valueField filterField
 
 // Literals.
 %nterm <CNode> dbPointer javascript symbol javascriptWScope int timestamp long double decimal 
@@ -235,12 +236,21 @@
 %nterm <CNode> abs ceil divide exponent floor ln log logten mod multiply pow round sqrt subtract trunc
 %nterm <std::pair<CNode::Fieldname, CNode>> onErrorArg onNullArg
 %nterm <std::vector<CNode>> expressions values
+%nterm <CNode> matchExpression filterFields filterVal
 
+%start start;
 //
 // Grammar rules
 //
 %%
 
+start: 
+    START_PIPELINE pipeline
+    | START_MATCH matchExpression {
+        *cst = CNode{$matchExpression};
+    }
+;
+
 // Entry point to pipeline parsing.
 pipeline:
     START_ARRAY stageList END_ARRAY {
@@ -367,6 +377,39 @@ projectionFieldname:
     invariableUserFieldname | stageAsUserFieldname | argAsUserFieldname | aggExprAsUserFieldname
 ;
 
+matchExpression:
+    START_OBJECT filterFields END_OBJECT {
+        $$ = CNode{CNode::ObjectChildren{std::pair{KeyFieldname::match, $filterFields}}};
+    }
+;
+
+filterFields:
+    %empty {
+        $$ = CNode::noopLeaf();
+    }
+    | filterFields[filterArg] filterField {
+        $$ = $filterArg;
+        $$.objectChildren().emplace_back($filterField);
+    }
+;
+
+filterField:
+    ID filterVal {
+        $$ = {KeyFieldname::id, $filterVal};
+    }
+    | filterFieldname filterVal {
+        $$ = {$filterFieldname, $filterVal};
+    }
+;
+
+filterVal:
+    value
+;
+
+filterFieldname:
+    invariableUserFieldname | stageAsUserFieldname | argAsUserFieldname | aggExprAsUserFieldname
+;
+
 invariableUserFieldname:
     FIELDNAME {
         $$ = UserFieldname{$1};
@@ -545,7 +588,7 @@ aggExprAsUserFieldname:
     }
 ;
 
-// Rules for literal non-terminals.
+// Rules for literal non-terminals. 
 string:
     STRING {
         $$ = CNode{UserString{$1}};
diff --git a/src/mongo/db/cst/pipeline_parser_gen.cpp b/src/mongo/db/cst/pipeline_parser_gen.cpp
index 6b78e3bc2e2..c04b637fa3e 100644
--- a/src/mongo/db/cst/pipeline_parser_gen.cpp
+++ b/src/mongo/db/cst/pipeline_parser_gen.cpp
@@ -1,4 +1,4 @@
-// A Bison parser, made by GNU Bison 3.6.3.
+// A Bison parser, made by GNU Bison 3.6.
 
 // Skeleton implementation for Bison LALR(1) parsers in C++
 
@@ -39,7 +39,7 @@
 
 
 // Unqualified %code blocks.
-#line 83 "pipeline_grammar.yy"
+#line 83 "src/mongo/db/cst/pipeline_grammar.yy"
 
 #include "mongo/db/cst/bson_lexer.h"
 #include "mongo/platform/decimal128.h"
@@ -54,7 +54,7 @@ void PipelineParserGen::error(const PipelineParserGen::location_type& loc, const
 }
 }  // namespace mongo
 
-#line 63 "pipeline_parser_gen.cpp"
+#line 63 "src/mongo/db/cst/pipeline_parser_gen.cpp"
 
 
 #ifndef YY_
@@ -145,9 +145,16 @@ void PipelineParserGen::error(const PipelineParserGen::location_type& loc, const
 #define YYERROR goto yyerrorlab
 #define YYRECOVERING() (!!yyerrstatus_)
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 namespace mongo {
-#line 156 "pipeline_parser_gen.cpp"
+#line 156 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+
+#if YYDEBUG || 0
+const char* PipelineParserGen::symbol_name(symbol_kind_type yysymbol) {
+    return yytname_[yysymbol];
+}
+#endif  // #if YYDEBUG || 0
+
 
 /// Build a parser object.
 PipelineParserGen::PipelineParserGen(BSONLexer& lexer_yyarg, CNode* cst_yyarg)
@@ -222,104 +229,108 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(YY_RVREF(stack_symbol_ty
             value.YY_MOVE_OR_COPY<BSONSymbol>(YY_MOVE(that.value));
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.YY_MOVE_OR_COPY<CNode>(YY_MOVE(that.value));
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.YY_MOVE_OR_COPY<CNode::Fieldname>(YY_MOVE(that.value));
             break;
 
@@ -367,11 +378,12 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(YY_RVREF(stack_symbol_ty
             value.YY_MOVE_OR_COPY<long long>(YY_MOVE(that.value));
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.YY_MOVE_OR_COPY<std::pair<CNode::Fieldname, CNode>>(YY_MOVE(that.value));
             break;
 
@@ -380,8 +392,8 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(YY_RVREF(stack_symbol_ty
             value.YY_MOVE_OR_COPY<std::string>(YY_MOVE(that.value));
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.YY_MOVE_OR_COPY<std::vector<CNode>>(YY_MOVE(that.value));
             break;
 
@@ -422,104 +434,108 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(state_type s, YY_MOVE_RE
             value.move<BSONSymbol>(YY_MOVE(that.value));
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.move<CNode>(YY_MOVE(that.value));
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.move<CNode::Fieldname>(YY_MOVE(that.value));
             break;
 
@@ -567,11 +583,12 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(state_type s, YY_MOVE_RE
             value.move<long long>(YY_MOVE(that.value));
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.move<std::pair<CNode::Fieldname, CNode>>(YY_MOVE(that.value));
             break;
 
@@ -580,8 +597,8 @@ PipelineParserGen::stack_symbol_type::stack_symbol_type(state_type s, YY_MOVE_RE
             value.move<std::string>(YY_MOVE(that.value));
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.move<std::vector<CNode>>(YY_MOVE(that.value));
             break;
 
@@ -622,104 +639,108 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.copy<BSONSymbol>(that.value);
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.copy<CNode>(that.value);
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.copy<CNode::Fieldname>(that.value);
             break;
 
@@ -767,11 +788,12 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.copy<long long>(that.value);
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.copy<std::pair<CNode::Fieldname, CNode>>(that.value);
             break;
 
@@ -780,8 +802,8 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.copy<std::string>(that.value);
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.copy<std::vector<CNode>>(that.value);
             break;
 
@@ -821,104 +843,108 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.move<BSONSymbol>(that.value);
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.move<CNode>(that.value);
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.move<CNode::Fieldname>(that.value);
             break;
 
@@ -966,11 +992,12 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.move<long long>(that.value);
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.move<std::pair<CNode::Fieldname, CNode>>(that.value);
             break;
 
@@ -979,8 +1006,8 @@ PipelineParserGen::stack_symbol_type& PipelineParserGen::stack_symbol_type::oper
             value.move<std::string>(that.value);
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.move<std::vector<CNode>>(that.value);
             break;
 
@@ -1010,7 +1037,7 @@ void PipelineParserGen::yy_print_(std::ostream& yyo, const basic_symbol<Base>& y
         yyo << "empty symbol";
     else {
         symbol_kind_type yykind = yysym.kind();
-        yyo << (yykind < YYNTOKENS ? "token" : "nterm") << ' ' << yysym.name() << " ("
+        yyo << (yykind < YYNTOKENS ? "token" : "nterm") << ' ' << symbol_name(yykind) << " ("
             << yysym.location << ": ";
         YYUSE(yykind);
         yyo << ')';
@@ -1231,104 +1258,108 @@ int PipelineParserGen::parse() {
                     yylhs.value.emplace<BSONSymbol>();
                     break;
 
-                case 97:   // dbPointer
-                case 98:   // javascript
-                case 99:   // symbol
-                case 100:  // javascriptWScope
-                case 101:  // int
-                case 102:  // timestamp
-                case 103:  // long
-                case 104:  // double
-                case 105:  // decimal
-                case 106:  // minKey
-                case 107:  // maxKey
-                case 108:  // value
-                case 109:  // string
-                case 110:  // binary
-                case 111:  // undefined
-                case 112:  // objectId
-                case 113:  // bool
-                case 114:  // date
-                case 115:  // null
-                case 116:  // regex
-                case 117:  // simpleValue
-                case 118:  // compoundValue
-                case 119:  // valueArray
-                case 120:  // valueObject
-                case 121:  // valueFields
-                case 122:  // stageList
-                case 123:  // stage
-                case 124:  // inhibitOptimization
-                case 125:  // unionWith
-                case 126:  // skip
-                case 127:  // limit
-                case 128:  // project
-                case 129:  // sample
-                case 130:  // projectFields
-                case 131:  // projection
-                case 132:  // num
-                case 133:  // expression
-                case 134:  // compoundExpression
-                case 135:  // exprFixedTwoArg
-                case 136:  // expressionArray
-                case 137:  // expressionObject
-                case 138:  // expressionFields
-                case 139:  // maths
-                case 140:  // add
-                case 141:  // atan2
-                case 142:  // boolExps
-                case 143:  // and
-                case 144:  // or
-                case 145:  // not
-                case 146:  // literalEscapes
-                case 147:  // const
-                case 148:  // literal
-                case 149:  // compExprs
-                case 150:  // cmp
-                case 151:  // eq
-                case 152:  // gt
-                case 153:  // gte
-                case 154:  // lt
-                case 155:  // lte
-                case 156:  // ne
-                case 157:  // typeExpression
-                case 158:  // typeValue
-                case 159:  // convert
-                case 160:  // toBool
-                case 161:  // toDate
-                case 162:  // toDecimal
-                case 163:  // toDouble
-                case 164:  // toInt
-                case 165:  // toLong
-                case 166:  // toObjectId
-                case 167:  // toString
-                case 168:  // type
-                case 169:  // abs
-                case 170:  // ceil
-                case 171:  // divide
-                case 172:  // exponent
-                case 173:  // floor
-                case 174:  // ln
-                case 175:  // log
-                case 176:  // logten
-                case 177:  // mod
-                case 178:  // multiply
-                case 179:  // pow
-                case 180:  // round
-                case 181:  // sqrt
-                case 182:  // subtract
-                case 183:  // trunc
+                case 101:  // dbPointer
+                case 102:  // javascript
+                case 103:  // symbol
+                case 104:  // javascriptWScope
+                case 105:  // int
+                case 106:  // timestamp
+                case 107:  // long
+                case 108:  // double
+                case 109:  // decimal
+                case 110:  // minKey
+                case 111:  // maxKey
+                case 112:  // value
+                case 113:  // string
+                case 114:  // binary
+                case 115:  // undefined
+                case 116:  // objectId
+                case 117:  // bool
+                case 118:  // date
+                case 119:  // null
+                case 120:  // regex
+                case 121:  // simpleValue
+                case 122:  // compoundValue
+                case 123:  // valueArray
+                case 124:  // valueObject
+                case 125:  // valueFields
+                case 126:  // stageList
+                case 127:  // stage
+                case 128:  // inhibitOptimization
+                case 129:  // unionWith
+                case 130:  // skip
+                case 131:  // limit
+                case 132:  // project
+                case 133:  // sample
+                case 134:  // projectFields
+                case 135:  // projection
+                case 136:  // num
+                case 137:  // expression
+                case 138:  // compoundExpression
+                case 139:  // exprFixedTwoArg
+                case 140:  // expressionArray
+                case 141:  // expressionObject
+                case 142:  // expressionFields
+                case 143:  // maths
+                case 144:  // add
+                case 145:  // atan2
+                case 146:  // boolExps
+                case 147:  // and
+                case 148:  // or
+                case 149:  // not
+                case 150:  // literalEscapes
+                case 151:  // const
+                case 152:  // literal
+                case 153:  // compExprs
+                case 154:  // cmp
+                case 155:  // eq
+                case 156:  // gt
+                case 157:  // gte
+                case 158:  // lt
+                case 159:  // lte
+                case 160:  // ne
+                case 161:  // typeExpression
+                case 162:  // typeValue
+                case 163:  // convert
+                case 164:  // toBool
+                case 165:  // toDate
+                case 166:  // toDecimal
+                case 167:  // toDouble
+                case 168:  // toInt
+                case 169:  // toLong
+                case 170:  // toObjectId
+                case 171:  // toString
+                case 172:  // type
+                case 173:  // abs
+                case 174:  // ceil
+                case 175:  // divide
+                case 176:  // exponent
+                case 177:  // floor
+                case 178:  // ln
+                case 179:  // log
+                case 180:  // logten
+                case 181:  // mod
+                case 182:  // multiply
+                case 183:  // pow
+                case 184:  // round
+                case 185:  // sqrt
+                case 186:  // subtract
+                case 187:  // trunc
+                case 192:  // matchExpression
+                case 193:  // filterFields
+                case 194:  // filterVal
                     yylhs.value.emplace<CNode>();
                     break;
 
-                case 86:  // projectionFieldname
-                case 87:  // expressionFieldname
-                case 88:  // stageAsUserFieldname
-                case 89:  // argAsUserFieldname
-                case 90:  // aggExprAsUserFieldname
-                case 91:  // invariableUserFieldname
-                case 92:  // idAsUserFieldname
-                case 93:  // valueFieldname
+                case 88:  // projectionFieldname
+                case 89:  // expressionFieldname
+                case 90:  // stageAsUserFieldname
+                case 91:  // filterFieldname
+                case 92:  // argAsUserFieldname
+                case 93:  // aggExprAsUserFieldname
+                case 94:  // invariableUserFieldname
+                case 95:  // idAsUserFieldname
+                case 96:  // valueFieldname
                     yylhs.value.emplace<CNode::Fieldname>();
                     break;
 
@@ -1376,11 +1407,12 @@ int PipelineParserGen::parse() {
                     yylhs.value.emplace<long long>();
                     break;
 
-                case 94:   // projectField
-                case 95:   // expressionField
-                case 96:   // valueField
-                case 184:  // onErrorArg
-                case 185:  // onNullArg
+                case 97:   // projectField
+                case 98:   // expressionField
+                case 99:   // valueField
+                case 100:  // filterField
+                case 188:  // onErrorArg
+                case 189:  // onNullArg
                     yylhs.value.emplace<std::pair<CNode::Fieldname, CNode>>();
                     break;
 
@@ -1389,8 +1421,8 @@ int PipelineParserGen::parse() {
                     yylhs.value.emplace<std::string>();
                     break;
 
-                case 186:  // expressions
-                case 187:  // values
+                case 190:  // expressions
+                case 191:  // values
                     yylhs.value.emplace<std::vector<CNode>>();
                     break;
 
@@ -1413,88 +1445,96 @@ int PipelineParserGen::parse() {
 #endif  // YY_EXCEPTIONS
             {
                 switch (yyn) {
-                    case 2:
-#line 246 "pipeline_grammar.yy"
+                    case 3:
+#line 249 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        *cst = CNode{YY_MOVE(yystack_[0].value.as<CNode>())};
+                    }
+#line 1522 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 4:
+#line 256 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         *cst = YY_MOVE(yystack_[1].value.as<CNode>());
                     }
-#line 1488 "pipeline_parser_gen.cpp"
+#line 1530 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 3:
-#line 252 "pipeline_grammar.yy"
+                    case 5:
+#line 262 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                     }
-#line 1494 "pipeline_parser_gen.cpp"
+#line 1536 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 4:
-#line 253 "pipeline_grammar.yy"
+                    case 6:
+#line 263 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{CNode::ArrayChildren{YY_MOVE(yystack_[2].value.as<CNode>())}};
                     }
-#line 1502 "pipeline_parser_gen.cpp"
+#line 1544 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 5:
-#line 261 "pipeline_grammar.yy"
+                    case 7:
+#line 271 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         lexer.sortObjTokens();
                     }
-#line 1508 "pipeline_parser_gen.cpp"
+#line 1550 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 7:
-#line 264 "pipeline_grammar.yy"
+                    case 9:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1514 "pipeline_parser_gen.cpp"
+#line 1556 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 8:
-#line 264 "pipeline_grammar.yy"
+                    case 10:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1520 "pipeline_parser_gen.cpp"
+#line 1562 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 9:
-#line 264 "pipeline_grammar.yy"
+                    case 11:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1526 "pipeline_parser_gen.cpp"
+#line 1568 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 10:
-#line 264 "pipeline_grammar.yy"
+                    case 12:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1532 "pipeline_parser_gen.cpp"
+#line 1574 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 11:
-#line 264 "pipeline_grammar.yy"
+                    case 13:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1538 "pipeline_parser_gen.cpp"
+#line 1580 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 12:
-#line 264 "pipeline_grammar.yy"
+                    case 14:
+#line 274 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1544 "pipeline_parser_gen.cpp"
+#line 1586 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 13:
-#line 267 "pipeline_grammar.yy"
+                    case 15:
+#line 277 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{std::pair{
                             KeyFieldname::sample,
@@ -1502,20 +1542,20 @@ int PipelineParserGen::parse() {
                                 {KeyFieldname::sizeArg, YY_MOVE(yystack_[1].value.as<CNode>())},
                             }}}}};
                     }
-#line 1556 "pipeline_parser_gen.cpp"
+#line 1598 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 14:
-#line 277 "pipeline_grammar.yy"
+                    case 16:
+#line 287 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             std::pair{KeyFieldname::inhibitOptimization, CNode::noopLeaf()}}};
                     }
-#line 1564 "pipeline_parser_gen.cpp"
+#line 1606 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 15:
-#line 283 "pipeline_grammar.yy"
+                    case 17:
+#line 293 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         auto pipeline = YY_MOVE(yystack_[1].value.as<CNode>());
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{std::pair{
@@ -1524,1353 +1564,1443 @@ int PipelineParserGen::parse() {
                                 {KeyFieldname::collArg, YY_MOVE(yystack_[3].value.as<CNode>())},
                                 {KeyFieldname::pipelineArg, std::move(pipeline)}}}}}};
                     }
-#line 1577 "pipeline_parser_gen.cpp"
+#line 1619 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 16:
-#line 293 "pipeline_grammar.yy"
+                    case 18:
+#line 303 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1583 "pipeline_parser_gen.cpp"
+#line 1625 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 17:
-#line 293 "pipeline_grammar.yy"
+                    case 19:
+#line 303 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1589 "pipeline_parser_gen.cpp"
+#line 1631 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 18:
-#line 293 "pipeline_grammar.yy"
+                    case 20:
+#line 303 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1595 "pipeline_parser_gen.cpp"
+#line 1637 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 19:
-#line 293 "pipeline_grammar.yy"
+                    case 21:
+#line 303 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1601 "pipeline_parser_gen.cpp"
+#line 1643 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 20:
-#line 297 "pipeline_grammar.yy"
+                    case 22:
+#line 307 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             std::pair{KeyFieldname::skip, YY_MOVE(yystack_[0].value.as<CNode>())}}};
                     }
-#line 1609 "pipeline_parser_gen.cpp"
+#line 1651 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 21:
-#line 302 "pipeline_grammar.yy"
+                    case 23:
+#line 312 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{std::pair{
                             KeyFieldname::limit, YY_MOVE(yystack_[0].value.as<CNode>())}}};
                     }
-#line 1617 "pipeline_parser_gen.cpp"
+#line 1659 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 22:
-#line 307 "pipeline_grammar.yy"
+                    case 24:
+#line 317 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{std::pair{
                             KeyFieldname::project, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 1625 "pipeline_parser_gen.cpp"
+#line 1667 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 23:
-#line 313 "pipeline_grammar.yy"
+                    case 25:
+#line 323 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode::noopLeaf();
                     }
-#line 1633 "pipeline_parser_gen.cpp"
+#line 1675 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 24:
-#line 316 "pipeline_grammar.yy"
+                    case 26:
+#line 326 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
                         yylhs.value.as<CNode>().objectChildren().emplace_back(
                             YY_MOVE(yystack_[0].value.as<std::pair<CNode::Fieldname, CNode>>()));
                     }
-#line 1642 "pipeline_parser_gen.cpp"
+#line 1684 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 25:
-#line 323 "pipeline_grammar.yy"
+                    case 27:
+#line 333 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
                             KeyFieldname::id, YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 1650 "pipeline_parser_gen.cpp"
+#line 1692 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 26:
-#line 326 "pipeline_grammar.yy"
+                    case 28:
+#line 336 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
                             YY_MOVE(yystack_[1].value.as<CNode::Fieldname>()),
                             YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 1658 "pipeline_parser_gen.cpp"
+#line 1700 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 27:
-#line 332 "pipeline_grammar.yy"
+                    case 29:
+#line 342 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1664 "pipeline_parser_gen.cpp"
+#line 1706 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 28:
-#line 333 "pipeline_grammar.yy"
+                    case 30:
+#line 343 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{NonZeroKey{YY_MOVE(yystack_[0].value.as<int>())}};
                     }
-#line 1672 "pipeline_parser_gen.cpp"
+#line 1714 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 29:
-#line 336 "pipeline_grammar.yy"
+                    case 31:
+#line 346 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::intZeroKey};
                     }
-#line 1680 "pipeline_parser_gen.cpp"
+#line 1722 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 30:
-#line 339 "pipeline_grammar.yy"
+                    case 32:
+#line 349 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{NonZeroKey{YY_MOVE(yystack_[0].value.as<long long>())}};
                     }
-#line 1688 "pipeline_parser_gen.cpp"
+#line 1730 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 31:
-#line 342 "pipeline_grammar.yy"
+                    case 33:
+#line 352 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::longZeroKey};
                     }
-#line 1696 "pipeline_parser_gen.cpp"
+#line 1738 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 32:
-#line 345 "pipeline_grammar.yy"
+                    case 34:
+#line 355 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{NonZeroKey{YY_MOVE(yystack_[0].value.as<double>())}};
                     }
-#line 1704 "pipeline_parser_gen.cpp"
+#line 1746 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 33:
-#line 348 "pipeline_grammar.yy"
+                    case 35:
+#line 358 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::doubleZeroKey};
                     }
-#line 1712 "pipeline_parser_gen.cpp"
+#line 1754 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 34:
-#line 351 "pipeline_grammar.yy"
+                    case 36:
+#line 361 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{NonZeroKey{YY_MOVE(yystack_[0].value.as<Decimal128>())}};
                     }
-#line 1720 "pipeline_parser_gen.cpp"
+#line 1762 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 35:
-#line 354 "pipeline_grammar.yy"
+                    case 37:
+#line 364 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::decimalZeroKey};
                     }
-#line 1728 "pipeline_parser_gen.cpp"
+#line 1770 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 36:
-#line 357 "pipeline_grammar.yy"
+                    case 38:
+#line 367 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::trueKey};
                     }
-#line 1736 "pipeline_parser_gen.cpp"
+#line 1778 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 37:
-#line 360 "pipeline_grammar.yy"
+                    case 39:
+#line 370 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{KeyValue::falseKey};
                     }
-#line 1744 "pipeline_parser_gen.cpp"
+#line 1786 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 38:
-#line 363 "pipeline_grammar.yy"
+                    case 40:
+#line 373 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 1750 "pipeline_parser_gen.cpp"
+#line 1792 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 39:
-#line 367 "pipeline_grammar.yy"
+                    case 41:
+#line 377 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 1756 "pipeline_parser_gen.cpp"
+#line 1798 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 40:
-#line 367 "pipeline_grammar.yy"
+                    case 42:
+#line 377 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 1762 "pipeline_parser_gen.cpp"
+#line 1804 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 41:
-#line 367 "pipeline_grammar.yy"
+                    case 43:
+#line 377 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 1768 "pipeline_parser_gen.cpp"
+#line 1810 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 42:
-#line 367 "pipeline_grammar.yy"
+                    case 44:
+#line 377 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 1774 "pipeline_parser_gen.cpp"
+#line 1816 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 43:
-#line 371 "pipeline_grammar.yy"
+                    case 45:
+#line 381 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{std::pair{
+                            KeyFieldname::match, YY_MOVE(yystack_[1].value.as<CNode>())}}};
+                    }
+#line 1824 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 46:
+#line 387 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode>() = CNode::noopLeaf();
+                    }
+#line 1832 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 47:
+#line 390 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
+                        yylhs.value.as<CNode>().objectChildren().emplace_back(
+                            YY_MOVE(yystack_[0].value.as<std::pair<CNode::Fieldname, CNode>>()));
+                    }
+#line 1841 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 48:
+#line 397 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
+                            KeyFieldname::id, YY_MOVE(yystack_[0].value.as<CNode>())};
+                    }
+#line 1849 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 49:
+#line 400 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
+                            YY_MOVE(yystack_[1].value.as<CNode::Fieldname>()),
+                            YY_MOVE(yystack_[0].value.as<CNode>())};
+                    }
+#line 1857 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 50:
+#line 406 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
+                    }
+#line 1863 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 51:
+#line 410 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode::Fieldname>() =
+                            YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
+                    }
+#line 1869 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 52:
+#line 410 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode::Fieldname>() =
+                            YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
+                    }
+#line 1875 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 53:
+#line 410 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode::Fieldname>() =
+                            YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
+                    }
+#line 1881 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 54:
+#line 410 "src/mongo/db/cst/pipeline_grammar.yy"
+                    {
+                        yylhs.value.as<CNode::Fieldname>() =
+                            YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
+                    }
+#line 1887 "src/mongo/db/cst/pipeline_parser_gen.cpp"
+                    break;
+
+                    case 55:
+#line 414 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             UserFieldname{YY_MOVE(yystack_[0].value.as<std::string>())};
                     }
-#line 1782 "pipeline_parser_gen.cpp"
+#line 1895 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 44:
-#line 379 "pipeline_grammar.yy"
+                    case 56:
+#line 422 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             UserFieldname{"$_internalInhibitOptimization"};
                     }
-#line 1790 "pipeline_parser_gen.cpp"
+#line 1903 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 45:
-#line 382 "pipeline_grammar.yy"
+                    case 57:
+#line 425 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$unionWith"};
                     }
-#line 1798 "pipeline_parser_gen.cpp"
+#line 1911 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 46:
-#line 385 "pipeline_grammar.yy"
+                    case 58:
+#line 428 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$skip"};
                     }
-#line 1806 "pipeline_parser_gen.cpp"
+#line 1919 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 47:
-#line 388 "pipeline_grammar.yy"
+                    case 59:
+#line 431 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$limit"};
                     }
-#line 1814 "pipeline_parser_gen.cpp"
+#line 1927 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 48:
-#line 391 "pipeline_grammar.yy"
+                    case 60:
+#line 434 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$project"};
                     }
-#line 1822 "pipeline_parser_gen.cpp"
+#line 1935 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 49:
-#line 394 "pipeline_grammar.yy"
+                    case 61:
+#line 437 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$sample"};
                     }
-#line 1830 "pipeline_parser_gen.cpp"
+#line 1943 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 50:
-#line 403 "pipeline_grammar.yy"
+                    case 62:
+#line 446 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"coll"};
                     }
-#line 1838 "pipeline_parser_gen.cpp"
+#line 1951 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 51:
-#line 406 "pipeline_grammar.yy"
+                    case 63:
+#line 449 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"pipeline"};
                     }
-#line 1846 "pipeline_parser_gen.cpp"
+#line 1959 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 52:
-#line 409 "pipeline_grammar.yy"
+                    case 64:
+#line 452 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"size"};
                     }
-#line 1854 "pipeline_parser_gen.cpp"
+#line 1967 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 53:
-#line 412 "pipeline_grammar.yy"
+                    case 65:
+#line 455 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"input"};
                     }
-#line 1862 "pipeline_parser_gen.cpp"
+#line 1975 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 54:
-#line 415 "pipeline_grammar.yy"
+                    case 66:
+#line 458 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"to"};
                     }
-#line 1870 "pipeline_parser_gen.cpp"
+#line 1983 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 55:
-#line 418 "pipeline_grammar.yy"
+                    case 67:
+#line 461 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"onError"};
                     }
-#line 1878 "pipeline_parser_gen.cpp"
+#line 1991 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 56:
-#line 421 "pipeline_grammar.yy"
+                    case 68:
+#line 464 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"onNull"};
                     }
-#line 1886 "pipeline_parser_gen.cpp"
+#line 1999 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 57:
-#line 429 "pipeline_grammar.yy"
+                    case 69:
+#line 472 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$add"};
                     }
-#line 1894 "pipeline_parser_gen.cpp"
+#line 2007 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 58:
-#line 432 "pipeline_grammar.yy"
+                    case 70:
+#line 475 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$atan2"};
                     }
-#line 1902 "pipeline_parser_gen.cpp"
+#line 2015 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 59:
-#line 435 "pipeline_grammar.yy"
+                    case 71:
+#line 478 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$and"};
                     }
-#line 1910 "pipeline_parser_gen.cpp"
+#line 2023 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 60:
-#line 438 "pipeline_grammar.yy"
+                    case 72:
+#line 481 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$const"};
                     }
-#line 1918 "pipeline_parser_gen.cpp"
+#line 2031 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 61:
-#line 441 "pipeline_grammar.yy"
+                    case 73:
+#line 484 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$literal"};
                     }
-#line 1926 "pipeline_parser_gen.cpp"
+#line 2039 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 62:
-#line 444 "pipeline_grammar.yy"
+                    case 74:
+#line 487 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$or"};
                     }
-#line 1934 "pipeline_parser_gen.cpp"
+#line 2047 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 63:
-#line 447 "pipeline_grammar.yy"
+                    case 75:
+#line 490 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$not"};
                     }
-#line 1942 "pipeline_parser_gen.cpp"
+#line 2055 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 64:
-#line 450 "pipeline_grammar.yy"
+                    case 76:
+#line 493 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$cmp"};
                     }
-#line 1950 "pipeline_parser_gen.cpp"
+#line 2063 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 65:
-#line 453 "pipeline_grammar.yy"
+                    case 77:
+#line 496 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$eq"};
                     }
-#line 1958 "pipeline_parser_gen.cpp"
+#line 2071 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 66:
-#line 456 "pipeline_grammar.yy"
+                    case 78:
+#line 499 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$gt"};
                     }
-#line 1966 "pipeline_parser_gen.cpp"
+#line 2079 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 67:
-#line 459 "pipeline_grammar.yy"
+                    case 79:
+#line 502 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$gte"};
                     }
-#line 1974 "pipeline_parser_gen.cpp"
+#line 2087 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 68:
-#line 462 "pipeline_grammar.yy"
+                    case 80:
+#line 505 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$lt"};
                     }
-#line 1982 "pipeline_parser_gen.cpp"
+#line 2095 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 69:
-#line 465 "pipeline_grammar.yy"
+                    case 81:
+#line 508 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$lte"};
                     }
-#line 1990 "pipeline_parser_gen.cpp"
+#line 2103 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 70:
-#line 468 "pipeline_grammar.yy"
+                    case 82:
+#line 511 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$ne"};
                     }
-#line 1998 "pipeline_parser_gen.cpp"
+#line 2111 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 71:
-#line 471 "pipeline_grammar.yy"
+                    case 83:
+#line 514 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$convert"};
                     }
-#line 2006 "pipeline_parser_gen.cpp"
+#line 2119 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 72:
-#line 474 "pipeline_grammar.yy"
+                    case 84:
+#line 517 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toBool"};
                     }
-#line 2014 "pipeline_parser_gen.cpp"
+#line 2127 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 73:
-#line 477 "pipeline_grammar.yy"
+                    case 85:
+#line 520 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toDate"};
                     }
-#line 2022 "pipeline_parser_gen.cpp"
+#line 2135 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 74:
-#line 480 "pipeline_grammar.yy"
+                    case 86:
+#line 523 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toDecimal"};
                     }
-#line 2030 "pipeline_parser_gen.cpp"
+#line 2143 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 75:
-#line 483 "pipeline_grammar.yy"
+                    case 87:
+#line 526 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toDouble"};
                     }
-#line 2038 "pipeline_parser_gen.cpp"
+#line 2151 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 76:
-#line 486 "pipeline_grammar.yy"
+                    case 88:
+#line 529 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toInt"};
                     }
-#line 2046 "pipeline_parser_gen.cpp"
+#line 2159 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 77:
-#line 489 "pipeline_grammar.yy"
+                    case 89:
+#line 532 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toLong"};
                     }
-#line 2054 "pipeline_parser_gen.cpp"
+#line 2167 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 78:
-#line 492 "pipeline_grammar.yy"
+                    case 90:
+#line 535 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toObjectId"};
                     }
-#line 2062 "pipeline_parser_gen.cpp"
+#line 2175 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 79:
-#line 495 "pipeline_grammar.yy"
+                    case 91:
+#line 538 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$toString"};
                     }
-#line 2070 "pipeline_parser_gen.cpp"
+#line 2183 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 80:
-#line 498 "pipeline_grammar.yy"
+                    case 92:
+#line 541 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$type"};
                     }
-#line 2078 "pipeline_parser_gen.cpp"
+#line 2191 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 81:
-#line 501 "pipeline_grammar.yy"
+                    case 93:
+#line 544 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$abs"};
                     }
-#line 2086 "pipeline_parser_gen.cpp"
+#line 2199 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 82:
-#line 504 "pipeline_grammar.yy"
+                    case 94:
+#line 547 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$ceil"};
                     }
-#line 2094 "pipeline_parser_gen.cpp"
+#line 2207 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 83:
-#line 507 "pipeline_grammar.yy"
+                    case 95:
+#line 550 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$divide"};
                     }
-#line 2102 "pipeline_parser_gen.cpp"
+#line 2215 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 84:
-#line 510 "pipeline_grammar.yy"
+                    case 96:
+#line 553 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$exp"};
                     }
-#line 2110 "pipeline_parser_gen.cpp"
+#line 2223 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 85:
-#line 513 "pipeline_grammar.yy"
+                    case 97:
+#line 556 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$floor"};
                     }
-#line 2118 "pipeline_parser_gen.cpp"
+#line 2231 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 86:
-#line 516 "pipeline_grammar.yy"
+                    case 98:
+#line 559 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$ln"};
                     }
-#line 2126 "pipeline_parser_gen.cpp"
+#line 2239 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 87:
-#line 519 "pipeline_grammar.yy"
+                    case 99:
+#line 562 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$log"};
                     }
-#line 2134 "pipeline_parser_gen.cpp"
+#line 2247 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 88:
-#line 522 "pipeline_grammar.yy"
+                    case 100:
+#line 565 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$log10"};
                     }
-#line 2142 "pipeline_parser_gen.cpp"
+#line 2255 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 89:
-#line 525 "pipeline_grammar.yy"
+                    case 101:
+#line 568 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$mod"};
                     }
-#line 2150 "pipeline_parser_gen.cpp"
+#line 2263 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 90:
-#line 528 "pipeline_grammar.yy"
+                    case 102:
+#line 571 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$multiply"};
                     }
-#line 2158 "pipeline_parser_gen.cpp"
+#line 2271 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 91:
-#line 531 "pipeline_grammar.yy"
+                    case 103:
+#line 574 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$pow"};
                     }
-#line 2166 "pipeline_parser_gen.cpp"
+#line 2279 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 92:
-#line 534 "pipeline_grammar.yy"
+                    case 104:
+#line 577 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$round"};
                     }
-#line 2174 "pipeline_parser_gen.cpp"
+#line 2287 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 93:
-#line 537 "pipeline_grammar.yy"
+                    case 105:
+#line 580 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$sqrt"};
                     }
-#line 2182 "pipeline_parser_gen.cpp"
+#line 2295 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 94:
-#line 540 "pipeline_grammar.yy"
+                    case 106:
+#line 583 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$subtract"};
                     }
-#line 2190 "pipeline_parser_gen.cpp"
+#line 2303 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 95:
-#line 543 "pipeline_grammar.yy"
+                    case 107:
+#line 586 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"$trunc"};
                     }
-#line 2198 "pipeline_parser_gen.cpp"
+#line 2311 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 96:
-#line 550 "pipeline_grammar.yy"
+                    case 108:
+#line 593 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserString{YY_MOVE(yystack_[0].value.as<std::string>())}};
                     }
-#line 2206 "pipeline_parser_gen.cpp"
+#line 2319 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 97:
-#line 556 "pipeline_grammar.yy"
+                    case 109:
+#line 599 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserBinary{YY_MOVE(yystack_[0].value.as<BSONBinData>())}};
                     }
-#line 2214 "pipeline_parser_gen.cpp"
+#line 2327 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 98:
-#line 562 "pipeline_grammar.yy"
+                    case 110:
+#line 605 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserUndefined{}};
                     }
-#line 2222 "pipeline_parser_gen.cpp"
+#line 2335 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 99:
-#line 568 "pipeline_grammar.yy"
+                    case 111:
+#line 611 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserObjectId{}};
                     }
-#line 2230 "pipeline_parser_gen.cpp"
+#line 2343 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 100:
-#line 574 "pipeline_grammar.yy"
+                    case 112:
+#line 617 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserDate{YY_MOVE(yystack_[0].value.as<Date_t>())}};
                     }
-#line 2238 "pipeline_parser_gen.cpp"
+#line 2351 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 101:
-#line 580 "pipeline_grammar.yy"
+                    case 113:
+#line 623 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserNull{}};
                     }
-#line 2246 "pipeline_parser_gen.cpp"
+#line 2359 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 102:
-#line 586 "pipeline_grammar.yy"
+                    case 114:
+#line 629 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserRegex{YY_MOVE(yystack_[0].value.as<BSONRegEx>())}};
                     }
-#line 2254 "pipeline_parser_gen.cpp"
+#line 2367 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 103:
-#line 592 "pipeline_grammar.yy"
+                    case 115:
+#line 635 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserDBPointer{YY_MOVE(yystack_[0].value.as<BSONDBRef>())}};
                     }
-#line 2262 "pipeline_parser_gen.cpp"
+#line 2375 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 104:
-#line 598 "pipeline_grammar.yy"
+                    case 116:
+#line 641 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserJavascript{YY_MOVE(yystack_[0].value.as<BSONCode>())}};
                     }
-#line 2270 "pipeline_parser_gen.cpp"
+#line 2383 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 105:
-#line 604 "pipeline_grammar.yy"
+                    case 117:
+#line 647 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserSymbol{YY_MOVE(yystack_[0].value.as<BSONSymbol>())}};
                     }
-#line 2278 "pipeline_parser_gen.cpp"
+#line 2391 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 106:
-#line 610 "pipeline_grammar.yy"
+                    case 118:
+#line 653 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserJavascriptWithScope{
                             YY_MOVE(yystack_[0].value.as<BSONCodeWScope>())}};
                     }
-#line 2286 "pipeline_parser_gen.cpp"
+#line 2399 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 107:
-#line 616 "pipeline_grammar.yy"
+                    case 119:
+#line 659 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserTimestamp{YY_MOVE(yystack_[0].value.as<Timestamp>())}};
                     }
-#line 2294 "pipeline_parser_gen.cpp"
+#line 2407 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 108:
-#line 622 "pipeline_grammar.yy"
+                    case 120:
+#line 665 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserMinKey{YY_MOVE(yystack_[0].value.as<UserMinKey>())}};
                     }
-#line 2302 "pipeline_parser_gen.cpp"
+#line 2415 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 109:
-#line 628 "pipeline_grammar.yy"
+                    case 121:
+#line 671 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserMaxKey{YY_MOVE(yystack_[0].value.as<UserMaxKey>())}};
                     }
-#line 2310 "pipeline_parser_gen.cpp"
+#line 2423 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 110:
-#line 634 "pipeline_grammar.yy"
+                    case 122:
+#line 677 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserInt{YY_MOVE(yystack_[0].value.as<int>())}};
                     }
-#line 2318 "pipeline_parser_gen.cpp"
+#line 2431 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 111:
-#line 637 "pipeline_grammar.yy"
+                    case 123:
+#line 680 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserInt{0}};
                     }
-#line 2326 "pipeline_parser_gen.cpp"
+#line 2439 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 112:
-#line 643 "pipeline_grammar.yy"
+                    case 124:
+#line 686 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserLong{YY_MOVE(yystack_[0].value.as<long long>())}};
                     }
-#line 2334 "pipeline_parser_gen.cpp"
+#line 2447 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 113:
-#line 646 "pipeline_grammar.yy"
+                    case 125:
+#line 689 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserLong{0ll}};
                     }
-#line 2342 "pipeline_parser_gen.cpp"
+#line 2455 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 114:
-#line 652 "pipeline_grammar.yy"
+                    case 126:
+#line 695 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserDouble{YY_MOVE(yystack_[0].value.as<double>())}};
                     }
-#line 2350 "pipeline_parser_gen.cpp"
+#line 2463 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 115:
-#line 655 "pipeline_grammar.yy"
+                    case 127:
+#line 698 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserDouble{0.0}};
                     }
-#line 2358 "pipeline_parser_gen.cpp"
+#line 2471 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 116:
-#line 661 "pipeline_grammar.yy"
+                    case 128:
+#line 704 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{UserDecimal{YY_MOVE(yystack_[0].value.as<Decimal128>())}};
                     }
-#line 2366 "pipeline_parser_gen.cpp"
+#line 2479 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 117:
-#line 664 "pipeline_grammar.yy"
+                    case 129:
+#line 707 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserDecimal{0.0}};
                     }
-#line 2374 "pipeline_parser_gen.cpp"
+#line 2487 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 118:
-#line 670 "pipeline_grammar.yy"
+                    case 130:
+#line 713 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserBoolean{true}};
                     }
-#line 2382 "pipeline_parser_gen.cpp"
+#line 2495 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 119:
-#line 673 "pipeline_grammar.yy"
+                    case 131:
+#line 716 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{UserBoolean{false}};
                     }
-#line 2390 "pipeline_parser_gen.cpp"
+#line 2503 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 120:
-#line 679 "pipeline_grammar.yy"
+                    case 132:
+#line 722 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2396 "pipeline_parser_gen.cpp"
+#line 2509 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 121:
-#line 680 "pipeline_grammar.yy"
+                    case 133:
+#line 723 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2402 "pipeline_parser_gen.cpp"
+#line 2515 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 122:
-#line 681 "pipeline_grammar.yy"
+                    case 134:
+#line 724 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2408 "pipeline_parser_gen.cpp"
+#line 2521 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 123:
-#line 682 "pipeline_grammar.yy"
+                    case 135:
+#line 725 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2414 "pipeline_parser_gen.cpp"
+#line 2527 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 124:
-#line 683 "pipeline_grammar.yy"
+                    case 136:
+#line 726 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2420 "pipeline_parser_gen.cpp"
+#line 2533 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 125:
-#line 684 "pipeline_grammar.yy"
+                    case 137:
+#line 727 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2426 "pipeline_parser_gen.cpp"
+#line 2539 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 126:
-#line 685 "pipeline_grammar.yy"
+                    case 138:
+#line 728 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2432 "pipeline_parser_gen.cpp"
+#line 2545 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 127:
-#line 686 "pipeline_grammar.yy"
+                    case 139:
+#line 729 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2438 "pipeline_parser_gen.cpp"
+#line 2551 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 128:
-#line 687 "pipeline_grammar.yy"
+                    case 140:
+#line 730 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2444 "pipeline_parser_gen.cpp"
+#line 2557 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 129:
-#line 688 "pipeline_grammar.yy"
+                    case 141:
+#line 731 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2450 "pipeline_parser_gen.cpp"
+#line 2563 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 130:
-#line 689 "pipeline_grammar.yy"
+                    case 142:
+#line 732 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2456 "pipeline_parser_gen.cpp"
+#line 2569 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 131:
-#line 690 "pipeline_grammar.yy"
+                    case 143:
+#line 733 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2462 "pipeline_parser_gen.cpp"
+#line 2575 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 132:
-#line 691 "pipeline_grammar.yy"
+                    case 144:
+#line 734 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2468 "pipeline_parser_gen.cpp"
+#line 2581 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 133:
-#line 692 "pipeline_grammar.yy"
+                    case 145:
+#line 735 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2474 "pipeline_parser_gen.cpp"
+#line 2587 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 134:
-#line 693 "pipeline_grammar.yy"
+                    case 146:
+#line 736 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2480 "pipeline_parser_gen.cpp"
+#line 2593 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 135:
-#line 694 "pipeline_grammar.yy"
+                    case 147:
+#line 737 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2486 "pipeline_parser_gen.cpp"
+#line 2599 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 136:
-#line 695 "pipeline_grammar.yy"
+                    case 148:
+#line 738 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2492 "pipeline_parser_gen.cpp"
+#line 2605 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 137:
-#line 696 "pipeline_grammar.yy"
+                    case 149:
+#line 739 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2498 "pipeline_parser_gen.cpp"
+#line 2611 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 138:
-#line 697 "pipeline_grammar.yy"
+                    case 150:
+#line 740 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2504 "pipeline_parser_gen.cpp"
+#line 2617 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 139:
-#line 704 "pipeline_grammar.yy"
+                    case 151:
+#line 747 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                     }
-#line 2510 "pipeline_parser_gen.cpp"
+#line 2623 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 140:
-#line 705 "pipeline_grammar.yy"
+                    case 152:
+#line 748 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::vector<CNode>>() =
                             YY_MOVE(yystack_[0].value.as<std::vector<CNode>>());
                         yylhs.value.as<std::vector<CNode>>().emplace_back(
                             YY_MOVE(yystack_[1].value.as<CNode>()));
                     }
-#line 2519 "pipeline_parser_gen.cpp"
+#line 2632 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 141:
-#line 712 "pipeline_grammar.yy"
+                    case 153:
+#line 755 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2525 "pipeline_parser_gen.cpp"
+#line 2638 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 142:
-#line 712 "pipeline_grammar.yy"
+                    case 154:
+#line 755 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2531 "pipeline_parser_gen.cpp"
+#line 2644 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 143:
-#line 716 "pipeline_grammar.yy"
+                    case 155:
+#line 759 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{CNode::ArrayChildren{YY_MOVE(yystack_[2].value.as<CNode>()),
                                                        YY_MOVE(yystack_[1].value.as<CNode>())}};
                     }
-#line 2539 "pipeline_parser_gen.cpp"
+#line 2652 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 144:
-#line 721 "pipeline_grammar.yy"
+                    case 156:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2545 "pipeline_parser_gen.cpp"
+#line 2658 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 145:
-#line 721 "pipeline_grammar.yy"
+                    case 157:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2551 "pipeline_parser_gen.cpp"
+#line 2664 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 146:
-#line 721 "pipeline_grammar.yy"
+                    case 158:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2557 "pipeline_parser_gen.cpp"
+#line 2670 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 147:
-#line 721 "pipeline_grammar.yy"
+                    case 159:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2563 "pipeline_parser_gen.cpp"
+#line 2676 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 148:
-#line 721 "pipeline_grammar.yy"
+                    case 160:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2569 "pipeline_parser_gen.cpp"
+#line 2682 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 149:
-#line 721 "pipeline_grammar.yy"
+                    case 161:
+#line 764 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2575 "pipeline_parser_gen.cpp"
+#line 2688 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 150:
-#line 722 "pipeline_grammar.yy"
+                    case 162:
+#line 765 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2581 "pipeline_parser_gen.cpp"
+#line 2694 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 151:
-#line 728 "pipeline_grammar.yy"
+                    case 163:
+#line 771 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{YY_MOVE(yystack_[1].value.as<std::vector<CNode>>())};
                     }
-#line 2589 "pipeline_parser_gen.cpp"
+#line 2702 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 152:
-#line 736 "pipeline_grammar.yy"
+                    case 164:
+#line 779 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
                     }
-#line 2597 "pipeline_parser_gen.cpp"
+#line 2710 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 153:
-#line 742 "pipeline_grammar.yy"
+                    case 165:
+#line 785 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode::noopLeaf();
                     }
-#line 2605 "pipeline_parser_gen.cpp"
+#line 2718 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 154:
-#line 745 "pipeline_grammar.yy"
+                    case 166:
+#line 788 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
                         yylhs.value.as<CNode>().objectChildren().emplace_back(
                             YY_MOVE(yystack_[0].value.as<std::pair<CNode::Fieldname, CNode>>()));
                     }
-#line 2614 "pipeline_parser_gen.cpp"
+#line 2727 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 155:
-#line 752 "pipeline_grammar.yy"
+                    case 167:
+#line 795 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
                             YY_MOVE(yystack_[1].value.as<CNode::Fieldname>()),
                             YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 2622 "pipeline_parser_gen.cpp"
+#line 2735 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 156:
-#line 759 "pipeline_grammar.yy"
+                    case 168:
+#line 802 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 2628 "pipeline_parser_gen.cpp"
+#line 2741 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 157:
-#line 759 "pipeline_grammar.yy"
+                    case 169:
+#line 802 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 2634 "pipeline_parser_gen.cpp"
+#line 2747 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 158:
-#line 759 "pipeline_grammar.yy"
+                    case 170:
+#line 802 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 2640 "pipeline_parser_gen.cpp"
+#line 2753 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 159:
-#line 759 "pipeline_grammar.yy"
+                    case 171:
+#line 802 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 2646 "pipeline_parser_gen.cpp"
+#line 2759 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 160:
-#line 763 "pipeline_grammar.yy"
+                    case 172:
+#line 806 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() = UserFieldname{"_id"};
                     }
-#line 2654 "pipeline_parser_gen.cpp"
+#line 2767 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 161:
-#line 769 "pipeline_grammar.yy"
+                    case 173:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2660 "pipeline_parser_gen.cpp"
+#line 2773 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 162:
-#line 769 "pipeline_grammar.yy"
+                    case 174:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2666 "pipeline_parser_gen.cpp"
+#line 2779 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 163:
-#line 769 "pipeline_grammar.yy"
+                    case 175:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2672 "pipeline_parser_gen.cpp"
+#line 2785 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 164:
-#line 769 "pipeline_grammar.yy"
+                    case 176:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2678 "pipeline_parser_gen.cpp"
+#line 2791 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 165:
-#line 769 "pipeline_grammar.yy"
+                    case 177:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2684 "pipeline_parser_gen.cpp"
+#line 2797 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 166:
-#line 769 "pipeline_grammar.yy"
+                    case 178:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2690 "pipeline_parser_gen.cpp"
+#line 2803 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 167:
-#line 769 "pipeline_grammar.yy"
+                    case 179:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2696 "pipeline_parser_gen.cpp"
+#line 2809 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 168:
-#line 769 "pipeline_grammar.yy"
+                    case 180:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2702 "pipeline_parser_gen.cpp"
+#line 2815 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 169:
-#line 769 "pipeline_grammar.yy"
+                    case 181:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2708 "pipeline_parser_gen.cpp"
+#line 2821 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 170:
-#line 769 "pipeline_grammar.yy"
+                    case 182:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2714 "pipeline_parser_gen.cpp"
+#line 2827 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 171:
-#line 769 "pipeline_grammar.yy"
+                    case 183:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2720 "pipeline_parser_gen.cpp"
+#line 2833 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 172:
-#line 769 "pipeline_grammar.yy"
+                    case 184:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2726 "pipeline_parser_gen.cpp"
+#line 2839 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 173:
-#line 769 "pipeline_grammar.yy"
+                    case 185:
+#line 812 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2732 "pipeline_parser_gen.cpp"
+#line 2845 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 174:
-#line 770 "pipeline_grammar.yy"
+                    case 186:
+#line 813 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2738 "pipeline_parser_gen.cpp"
+#line 2851 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 175:
-#line 770 "pipeline_grammar.yy"
+                    case 187:
+#line 813 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2744 "pipeline_parser_gen.cpp"
+#line 2857 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 176:
-#line 770 "pipeline_grammar.yy"
+                    case 188:
+#line 813 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2750 "pipeline_parser_gen.cpp"
+#line 2863 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 177:
-#line 770 "pipeline_grammar.yy"
+                    case 189:
+#line 813 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2756 "pipeline_parser_gen.cpp"
+#line 2869 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 178:
-#line 774 "pipeline_grammar.yy"
+                    case 190:
+#line 817 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::add,
@@ -2881,107 +3011,107 @@ int PipelineParserGen::parse() {
                             yylhs.value.as<CNode>().objectChildren()[0].second.arrayChildren();
                         array.insert(array.end(), others.begin(), others.end());
                     }
-#line 2768 "pipeline_parser_gen.cpp"
+#line 2881 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 179:
-#line 784 "pipeline_grammar.yy"
+                    case 191:
+#line 827 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::atan2, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2777 "pipeline_parser_gen.cpp"
+#line 2890 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 180:
-#line 790 "pipeline_grammar.yy"
+                    case 192:
+#line 833 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::abs, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2785 "pipeline_parser_gen.cpp"
+#line 2898 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 181:
-#line 795 "pipeline_grammar.yy"
+                    case 193:
+#line 838 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::ceil, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2793 "pipeline_parser_gen.cpp"
+#line 2906 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 182:
-#line 800 "pipeline_grammar.yy"
+                    case 194:
+#line 843 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::divide,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2802 "pipeline_parser_gen.cpp"
+#line 2915 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 183:
-#line 806 "pipeline_grammar.yy"
+                    case 195:
+#line 849 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::exponent, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2810 "pipeline_parser_gen.cpp"
+#line 2923 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 184:
-#line 811 "pipeline_grammar.yy"
+                    case 196:
+#line 854 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::floor, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2818 "pipeline_parser_gen.cpp"
+#line 2931 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 185:
-#line 816 "pipeline_grammar.yy"
+                    case 197:
+#line 859 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::ln, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2826 "pipeline_parser_gen.cpp"
+#line 2939 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 186:
-#line 821 "pipeline_grammar.yy"
+                    case 198:
+#line 864 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::log,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2835 "pipeline_parser_gen.cpp"
+#line 2948 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 187:
-#line 827 "pipeline_grammar.yy"
+                    case 199:
+#line 870 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::logten, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2843 "pipeline_parser_gen.cpp"
+#line 2956 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 188:
-#line 832 "pipeline_grammar.yy"
+                    case 200:
+#line 875 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::mod,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2852 "pipeline_parser_gen.cpp"
+#line 2965 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 189:
-#line 838 "pipeline_grammar.yy"
+                    case 201:
+#line 881 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::multiply,
@@ -2992,88 +3122,88 @@ int PipelineParserGen::parse() {
                             yylhs.value.as<CNode>().objectChildren()[0].second.arrayChildren();
                         array.insert(array.end(), others.begin(), others.end());
                     }
-#line 2864 "pipeline_parser_gen.cpp"
+#line 2977 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 190:
-#line 847 "pipeline_grammar.yy"
+                    case 202:
+#line 890 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::pow,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2873 "pipeline_parser_gen.cpp"
+#line 2986 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 191:
-#line 853 "pipeline_grammar.yy"
+                    case 203:
+#line 896 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::round,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2882 "pipeline_parser_gen.cpp"
+#line 2995 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 192:
-#line 859 "pipeline_grammar.yy"
+                    case 204:
+#line 902 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::sqrt, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 2890 "pipeline_parser_gen.cpp"
+#line 3003 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 193:
-#line 864 "pipeline_grammar.yy"
+                    case 205:
+#line 907 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::subtract,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2899 "pipeline_parser_gen.cpp"
+#line 3012 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 194:
-#line 870 "pipeline_grammar.yy"
+                    case 206:
+#line 913 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::trunc,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[3].value.as<CNode>()),
                                                         YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2908 "pipeline_parser_gen.cpp"
+#line 3021 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 195:
-#line 876 "pipeline_grammar.yy"
+                    case 207:
+#line 919 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2914 "pipeline_parser_gen.cpp"
+#line 3027 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 196:
-#line 876 "pipeline_grammar.yy"
+                    case 208:
+#line 919 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2920 "pipeline_parser_gen.cpp"
+#line 3033 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 197:
-#line 876 "pipeline_grammar.yy"
+                    case 209:
+#line 919 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2926 "pipeline_parser_gen.cpp"
+#line 3039 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 198:
-#line 880 "pipeline_grammar.yy"
+                    case 210:
+#line 923 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::andExpr,
@@ -3084,11 +3214,11 @@ int PipelineParserGen::parse() {
                             yylhs.value.as<CNode>().objectChildren()[0].second.arrayChildren();
                         array.insert(array.end(), others.begin(), others.end());
                     }
-#line 2938 "pipeline_parser_gen.cpp"
+#line 3051 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 199:
-#line 890 "pipeline_grammar.yy"
+                    case 211:
+#line 933 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::orExpr,
@@ -3099,472 +3229,472 @@ int PipelineParserGen::parse() {
                             yylhs.value.as<CNode>().objectChildren()[0].second.arrayChildren();
                         array.insert(array.end(), others.begin(), others.end());
                     }
-#line 2950 "pipeline_parser_gen.cpp"
+#line 3063 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 200:
-#line 900 "pipeline_grammar.yy"
+                    case 212:
+#line 943 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::notExpr,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2959 "pipeline_parser_gen.cpp"
+#line 3072 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 201:
-#line 907 "pipeline_grammar.yy"
+                    case 213:
+#line 950 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2965 "pipeline_parser_gen.cpp"
+#line 3078 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 202:
-#line 907 "pipeline_grammar.yy"
+                    case 214:
+#line 950 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2971 "pipeline_parser_gen.cpp"
+#line 3084 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 203:
-#line 911 "pipeline_grammar.yy"
+                    case 215:
+#line 954 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::constExpr,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2980 "pipeline_parser_gen.cpp"
+#line 3093 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 204:
-#line 918 "pipeline_grammar.yy"
+                    case 216:
+#line 961 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::literal,
                              CNode{CNode::ArrayChildren{YY_MOVE(yystack_[2].value.as<CNode>())}}}}};
                     }
-#line 2989 "pipeline_parser_gen.cpp"
+#line 3102 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 205:
-#line 925 "pipeline_grammar.yy"
+                    case 217:
+#line 968 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 2995 "pipeline_parser_gen.cpp"
+#line 3108 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 206:
-#line 925 "pipeline_grammar.yy"
+                    case 218:
+#line 968 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3001 "pipeline_parser_gen.cpp"
+#line 3114 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 207:
-#line 929 "pipeline_grammar.yy"
+                    case 219:
+#line 972 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3007 "pipeline_parser_gen.cpp"
+#line 3120 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 208:
-#line 929 "pipeline_grammar.yy"
+                    case 220:
+#line 972 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3013 "pipeline_parser_gen.cpp"
+#line 3126 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 209:
-#line 933 "pipeline_grammar.yy"
+                    case 221:
+#line 976 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() =
                             CNode{YY_MOVE(yystack_[1].value.as<std::vector<CNode>>())};
                     }
-#line 3021 "pipeline_parser_gen.cpp"
+#line 3134 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 210:
-#line 939 "pipeline_grammar.yy"
+                    case 222:
+#line 982 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                     }
-#line 3027 "pipeline_parser_gen.cpp"
+#line 3140 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 211:
-#line 940 "pipeline_grammar.yy"
+                    case 223:
+#line 983 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::vector<CNode>>() =
                             YY_MOVE(yystack_[0].value.as<std::vector<CNode>>());
                         yylhs.value.as<std::vector<CNode>>().emplace_back(
                             YY_MOVE(yystack_[1].value.as<CNode>()));
                     }
-#line 3036 "pipeline_parser_gen.cpp"
+#line 3149 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 212:
-#line 947 "pipeline_grammar.yy"
+                    case 224:
+#line 990 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
                     }
-#line 3044 "pipeline_parser_gen.cpp"
+#line 3157 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 213:
-#line 953 "pipeline_grammar.yy"
+                    case 225:
+#line 996 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode::noopLeaf();
                     }
-#line 3052 "pipeline_parser_gen.cpp"
+#line 3165 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 214:
-#line 956 "pipeline_grammar.yy"
+                    case 226:
+#line 999 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[1].value.as<CNode>());
                         yylhs.value.as<CNode>().objectChildren().emplace_back(
                             YY_MOVE(yystack_[0].value.as<std::pair<CNode::Fieldname, CNode>>()));
                     }
-#line 3061 "pipeline_parser_gen.cpp"
+#line 3174 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 215:
-#line 963 "pipeline_grammar.yy"
+                    case 227:
+#line 1006 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = {
                             YY_MOVE(yystack_[1].value.as<CNode::Fieldname>()),
                             YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 3069 "pipeline_parser_gen.cpp"
+#line 3182 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 216:
-#line 970 "pipeline_grammar.yy"
+                    case 228:
+#line 1013 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 3075 "pipeline_parser_gen.cpp"
+#line 3188 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 217:
-#line 971 "pipeline_grammar.yy"
+                    case 229:
+#line 1014 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 3081 "pipeline_parser_gen.cpp"
+#line 3194 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 218:
-#line 972 "pipeline_grammar.yy"
+                    case 230:
+#line 1015 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 3087 "pipeline_parser_gen.cpp"
+#line 3200 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 219:
-#line 973 "pipeline_grammar.yy"
+                    case 231:
+#line 1016 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 3093 "pipeline_parser_gen.cpp"
+#line 3206 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 220:
-#line 974 "pipeline_grammar.yy"
+                    case 232:
+#line 1017 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode::Fieldname>() =
                             YY_MOVE(yystack_[0].value.as<CNode::Fieldname>());
                     }
-#line 3099 "pipeline_parser_gen.cpp"
+#line 3212 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 221:
-#line 977 "pipeline_grammar.yy"
+                    case 233:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3105 "pipeline_parser_gen.cpp"
+#line 3218 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 222:
-#line 977 "pipeline_grammar.yy"
+                    case 234:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3111 "pipeline_parser_gen.cpp"
+#line 3224 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 223:
-#line 977 "pipeline_grammar.yy"
+                    case 235:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3117 "pipeline_parser_gen.cpp"
+#line 3230 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 224:
-#line 977 "pipeline_grammar.yy"
+                    case 236:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3123 "pipeline_parser_gen.cpp"
+#line 3236 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 225:
-#line 977 "pipeline_grammar.yy"
+                    case 237:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3129 "pipeline_parser_gen.cpp"
+#line 3242 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 226:
-#line 977 "pipeline_grammar.yy"
+                    case 238:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3135 "pipeline_parser_gen.cpp"
+#line 3248 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 227:
-#line 977 "pipeline_grammar.yy"
+                    case 239:
+#line 1020 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3141 "pipeline_parser_gen.cpp"
+#line 3254 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 228:
-#line 979 "pipeline_grammar.yy"
+                    case 240:
+#line 1022 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::cmp, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3150 "pipeline_parser_gen.cpp"
+#line 3263 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 229:
-#line 984 "pipeline_grammar.yy"
+                    case 241:
+#line 1027 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::eq, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3159 "pipeline_parser_gen.cpp"
+#line 3272 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 230:
-#line 989 "pipeline_grammar.yy"
+                    case 242:
+#line 1032 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::gt, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3168 "pipeline_parser_gen.cpp"
+#line 3281 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 231:
-#line 994 "pipeline_grammar.yy"
+                    case 243:
+#line 1037 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::gte, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3177 "pipeline_parser_gen.cpp"
+#line 3290 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 232:
-#line 999 "pipeline_grammar.yy"
+                    case 244:
+#line 1042 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::lt, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3186 "pipeline_parser_gen.cpp"
+#line 3299 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 233:
-#line 1004 "pipeline_grammar.yy"
+                    case 245:
+#line 1047 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::lte, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3195 "pipeline_parser_gen.cpp"
+#line 3308 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 234:
-#line 1009 "pipeline_grammar.yy"
+                    case 246:
+#line 1052 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::ne, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3204 "pipeline_parser_gen.cpp"
+#line 3317 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 235:
-#line 1015 "pipeline_grammar.yy"
+                    case 247:
+#line 1058 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3210 "pipeline_parser_gen.cpp"
+#line 3323 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 236:
-#line 1016 "pipeline_grammar.yy"
+                    case 248:
+#line 1059 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3216 "pipeline_parser_gen.cpp"
+#line 3329 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 237:
-#line 1017 "pipeline_grammar.yy"
+                    case 249:
+#line 1060 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3222 "pipeline_parser_gen.cpp"
+#line 3335 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 238:
-#line 1018 "pipeline_grammar.yy"
+                    case 250:
+#line 1061 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3228 "pipeline_parser_gen.cpp"
+#line 3341 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 239:
-#line 1019 "pipeline_grammar.yy"
+                    case 251:
+#line 1062 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3234 "pipeline_parser_gen.cpp"
+#line 3347 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 240:
-#line 1020 "pipeline_grammar.yy"
+                    case 252:
+#line 1063 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3240 "pipeline_parser_gen.cpp"
+#line 3353 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 241:
-#line 1021 "pipeline_grammar.yy"
+                    case 253:
+#line 1064 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3246 "pipeline_parser_gen.cpp"
+#line 3359 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 242:
-#line 1022 "pipeline_grammar.yy"
+                    case 254:
+#line 1065 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3252 "pipeline_parser_gen.cpp"
+#line 3365 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 243:
-#line 1023 "pipeline_grammar.yy"
+                    case 255:
+#line 1066 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3258 "pipeline_parser_gen.cpp"
+#line 3371 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 244:
-#line 1024 "pipeline_grammar.yy"
+                    case 256:
+#line 1067 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3264 "pipeline_parser_gen.cpp"
+#line 3377 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 245:
-#line 1030 "pipeline_grammar.yy"
+                    case 257:
+#line 1073 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3270 "pipeline_parser_gen.cpp"
+#line 3383 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 246:
-#line 1030 "pipeline_grammar.yy"
+                    case 258:
+#line 1073 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3276 "pipeline_parser_gen.cpp"
+#line 3389 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 247:
-#line 1030 "pipeline_grammar.yy"
+                    case 259:
+#line 1073 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3282 "pipeline_parser_gen.cpp"
+#line 3395 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 248:
-#line 1030 "pipeline_grammar.yy"
+                    case 260:
+#line 1073 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3288 "pipeline_parser_gen.cpp"
+#line 3401 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 249:
-#line 1030 "pipeline_grammar.yy"
+                    case 261:
+#line 1073 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = YY_MOVE(yystack_[0].value.as<CNode>());
                     }
-#line 3294 "pipeline_parser_gen.cpp"
+#line 3407 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 250:
-#line 1034 "pipeline_grammar.yy"
+                    case 262:
+#line 1077 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() =
                             std::pair{KeyFieldname::onErrorArg, CNode{KeyValue::absentKey}};
                     }
-#line 3302 "pipeline_parser_gen.cpp"
+#line 3415 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 251:
-#line 1037 "pipeline_grammar.yy"
+                    case 263:
+#line 1080 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = std::pair{
                             KeyFieldname::onErrorArg, YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 3310 "pipeline_parser_gen.cpp"
+#line 3423 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 252:
-#line 1044 "pipeline_grammar.yy"
+                    case 264:
+#line 1087 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() =
                             std::pair{KeyFieldname::onNullArg, CNode{KeyValue::absentKey}};
                     }
-#line 3318 "pipeline_parser_gen.cpp"
+#line 3431 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 253:
-#line 1047 "pipeline_grammar.yy"
+                    case 265:
+#line 1090 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<std::pair<CNode::Fieldname, CNode>>() = std::pair{
                             KeyFieldname::onNullArg, YY_MOVE(yystack_[0].value.as<CNode>())};
                     }
-#line 3326 "pipeline_parser_gen.cpp"
+#line 3439 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 254:
-#line 1053 "pipeline_grammar.yy"
+                    case 266:
+#line 1096 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::convert,
@@ -3576,92 +3706,92 @@ int PipelineParserGen::parse() {
                                  YY_MOVE(yystack_[2]
                                              .value.as<std::pair<CNode::Fieldname, CNode>>())}}}}};
                     }
-#line 3337 "pipeline_parser_gen.cpp"
+#line 3450 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 255:
-#line 1062 "pipeline_grammar.yy"
+                    case 267:
+#line 1105 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toBool, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3345 "pipeline_parser_gen.cpp"
+#line 3458 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 256:
-#line 1067 "pipeline_grammar.yy"
+                    case 268:
+#line 1110 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toDate, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3353 "pipeline_parser_gen.cpp"
+#line 3466 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 257:
-#line 1072 "pipeline_grammar.yy"
+                    case 269:
+#line 1115 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toDecimal, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3361 "pipeline_parser_gen.cpp"
+#line 3474 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 258:
-#line 1077 "pipeline_grammar.yy"
+                    case 270:
+#line 1120 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toDouble, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3369 "pipeline_parser_gen.cpp"
+#line 3482 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 259:
-#line 1082 "pipeline_grammar.yy"
+                    case 271:
+#line 1125 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toInt, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3377 "pipeline_parser_gen.cpp"
+#line 3490 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 260:
-#line 1087 "pipeline_grammar.yy"
+                    case 272:
+#line 1130 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toLong, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3385 "pipeline_parser_gen.cpp"
+#line 3498 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 261:
-#line 1092 "pipeline_grammar.yy"
+                    case 273:
+#line 1135 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toObjectId, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3393 "pipeline_parser_gen.cpp"
+#line 3506 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 262:
-#line 1097 "pipeline_grammar.yy"
+                    case 274:
+#line 1140 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::toString, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3401 "pipeline_parser_gen.cpp"
+#line 3514 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
-                    case 263:
-#line 1102 "pipeline_grammar.yy"
+                    case 275:
+#line 1145 "src/mongo/db/cst/pipeline_grammar.yy"
                     {
                         yylhs.value.as<CNode>() = CNode{CNode::ObjectChildren{
                             {KeyFieldname::type, YY_MOVE(yystack_[1].value.as<CNode>())}}};
                     }
-#line 3409 "pipeline_parser_gen.cpp"
+#line 3522 "src/mongo/db/cst/pipeline_parser_gen.cpp"
                     break;
 
 
-#line 3413 "pipeline_parser_gen.cpp"
+#line 3526 "src/mongo/db/cst/pipeline_parser_gen.cpp"
 
                     default:
                         break;
@@ -3825,201 +3955,207 @@ void PipelineParserGen::error(const syntax_error& yyexc) {
     error(yyexc.location, yyexc.what());
 }
 
-#if YYDEBUG || 0
-const char* PipelineParserGen::symbol_name(symbol_kind_type yysymbol) {
-    return yytname_[yysymbol];
-}
-#endif  // #if YYDEBUG || 0
-
 
-const short PipelineParserGen::yypact_ninf_ = -226;
+const short PipelineParserGen::yypact_ninf_ = -274;
 
 const signed char PipelineParserGen::yytable_ninf_ = -1;
 
 const short PipelineParserGen::yypact_[] = {
-    35,   39,   44,   77,   41,   -226, 43,   61,   51,   52,   61,   -226, 60,   -226, -226, -226,
-    -226, -226, -226, -226, 62,   -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, 45,   -226, 48,   70,   39,   -226, 278,  61,   7,    -226, -226, -226, 40,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, 40,   -226, -226, -226, -226, -226, 71,   -226, 55,   487,  179,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -2,   76,   81,
-    82,   83,   84,   92,   93,   81,   81,   81,   81,   81,   81,   81,   -226, 179,  179,  179,
-    179,  179,  179,  179,  179,  179,  179,  179,  94,   179,  179,  179,  95,   179,  96,   97,
-    98,   100,  179,  101,  104,  443,  -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, 179,  -226, 108,  78,   179,  179,  113,
-    179,  197,  197,  179,  179,  119,  129,  130,  131,  133,  141,  142,  85,   144,  146,  148,
-    151,  152,  153,  154,  155,  158,  159,  160,  179,  170,  171,  172,  179,  173,  179,  179,
-    179,  179,  174,  179,  179,  -226, -226, 179,  -226, -226, -226, -226, -226, -226, -226, -226,
-    179,  179,  -226, 179,  -226, 197,  175,  -226, -226, -226, -226, 180,  179,  187,  -226, -226,
-    -226, -226, -226, -226, -226, 179,  -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, 179,  -226, -226, -226, 179,  -226, 179,  179,  179,  179,  -226, 179,  179,  -226, 179,
-    189,  179,  380,  197,  193,  176,  181,  179,  199,  138,  198,  205,  206,  179,  207,  208,
-    209,  210,  211,  -226, 212,  -226, -226, -226, -226, -226, -226, 197,  -226, -226, -226, -226,
-    -226, 213,  -226, 116,  216,  217,  218,  219,  220,  222,  223,  224,  225,  226,  -226, 227,
-    -226, -226, -226, -226, -226, 115,  -226, -226, -226, 228,  -226, -226, -226, -226, -226, -226,
-    -226, 179,  168,  -226, -226, 179,  230,  -226, 231,  -226};
+    -64,  13,   44,   51,   50,   -274, -274, -274, -274, 166,  48,   292,  52,   81,   53,   55,
+    81,   -274, 57,   -274, -274, -274, -274, -274, -274, -274, -274, 165,  -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, 165,  -274, -274, -274, -274, 59,   -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, 37,   -274, 45,   61,   50,   -274, 165,  -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, 392,  81,   1,    -274, -274, 455,  165,  64,
+    -274, 124,  124,  -274, -274, -274, -274, -274, 67,   54,   -274, -274, -274, -274, -274, -274,
+    -274, 165,  -274, -274, -274, 562,  211,  -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, 3,    -274, 69,   71,   72,   73,   75,   76,   77,   71,   71,   71,
+    71,   71,   71,   71,   -274, 211,  211,  211,  211,  211,  211,  211,  211,  211,  211,  211,
+    78,   211,  211,  211,  80,   211,  82,   89,   90,   91,   211,  93,   98,   518,  -274, 211,
+    -274, 100,  104,  211,  211,  106,  211,  165,  165,  211,  211,  108,  109,  111,  114,  117,
+    119,  120,  24,   121,  122,  126,  135,  140,  154,  156,  160,  161,  162,  163,  211,  167,
+    168,  175,  211,  182,  211,  211,  211,  211,  183,  211,  211,  -274, 211,  -274, -274, -274,
+    -274, -274, -274, -274, -274, 211,  211,  -274, 211,  190,  193,  211,  194,  -274, -274, -274,
+    -274, -274, -274, -274, 211,  -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    211,  -274, -274, -274, 211,  -274, 211,  211,  211,  211,  -274, 211,  211,  -274, 211,  195,
+    211,  185,  186,  211,  199,  65,   201,  202,  204,  211,  205,  206,  209,  212,  219,  -274,
+    220,  -274, -274, 221,  -274, 184,  213,  224,  225,  244,  226,  248,  249,  250,  251,  252,
+    253,  -274, -274, -274, -274, -274, 105,  -274, -274, -274, 254,  -274, -274, -274, -274, -274,
+    -274, -274, 211,  123,  -274, -274, 211,  256,  -274, 257,  -274};
 
 const short PipelineParserGen::yydefact_[] = {
-    0,   3,   0,   0,   0,   1,   0,   0,   0,   0,   0,   5,   0,   7,   8,   9,   10,  11,  12,
-    2,   0,   111, 113, 115, 117, 110, 112, 114, 116, 16,  17,  18,  19,  21,  23,  0,   20,  0,
-    0,   3,   14,  0,   0,   0,   6,   4,   22,  0,   44,  47,  48,  49,  46,  45,  50,  51,  52,
-    57,  58,  59,  60,  61,  62,  63,  64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,
-    76,  77,  78,  79,  80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,
-    95,  53,  54,  55,  56,  43,  0,   40,  41,  42,  39,  24,  0,   96,  0,   153, 139, 29,  31,
-    33,  35,  36,  37,  28,  30,  32,  34,  27,  25,  38,  144, 145, 146, 161, 162, 147, 195, 196,
-    197, 148, 201, 202, 149, 221, 222, 223, 224, 225, 226, 227, 150, 235, 236, 237, 238, 239, 240,
-    241, 242, 243, 244, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177,
-    26,  13,  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   5,   0,
+    0,   0,   0,   0,   5,   2,   46,  3,   1,   0,   0,   0,   0,   0,   0,   0,   0,   7,   0,
+    9,   10,  11,  12,  13,  14,  4,   45,  0,   56,  59,  60,  61,  58,  57,  62,  63,  64,  69,
+    70,  71,  72,  73,  74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,  85,  86,  87,  88,
+    89,  90,  91,  92,  93,  94,  95,  96,  97,  98,  99,  100, 101, 102, 103, 104, 105, 106, 107,
+    65,  66,  67,  68,  55,  52,  0,   53,  54,  51,  47,  0,   123, 125, 127, 129, 122, 124, 126,
+    128, 18,  19,  20,  21,  23,  25,  0,   22,  0,   0,   5,   225, 222, 130, 131, 108, 109, 110,
+    111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 139, 140, 141, 142, 143, 148, 144, 145,
+    146, 149, 150, 50,  132, 133, 134, 135, 147, 136, 137, 138, 217, 218, 219, 220, 48,  49,  16,
+    0,   0,   0,   8,   6,   0,   222, 0,   24,  0,   0,   42,  43,  44,  41,  26,  0,   0,   224,
+    172, 229, 230, 231, 228, 232, 0,   226, 223, 221, 165, 151, 31,  33,  35,  37,  38,  39,  30,
+    32,  34,  36,  29,  27,  40,  156, 157, 158, 173, 174, 159, 207, 208, 209, 160, 213, 214, 161,
+    233, 234, 235, 236, 237, 238, 239, 162, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 175,
+    176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 28,  15,  0,   227, 0,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   7,   0,   0,   0,   0,   0,
     0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-    0,   0,   0,   0,   0,   118, 119, 97,  98,  99,  100, 101, 102, 103, 104, 105, 106, 107, 108,
-    109, 127, 128, 129, 130, 131, 136, 132, 133, 134, 137, 138, 120, 121, 122, 123, 135, 124, 125,
-    126, 141, 139, 142, 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   153, 151, 154, 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
     0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-    0,   0,   0,   0,   0,   0,   0,   0,   152, 160, 0,   157, 158, 156, 159, 154, 140, 151, 15,
-    0,   0,   179, 0,   213, 210, 0,   205, 206, 207, 208, 0,   0,   0,   228, 229, 230, 231, 232,
-    233, 234, 0,   255, 256, 257, 258, 259, 260, 261, 262, 263, 180, 181, 0,   183, 184, 185, 0,
-    187, 0,   0,   0,   0,   192, 0,   0,   155, 139, 0,   139, 0,   210, 0,   0,   0,   139, 0,
-    0,   0,   0,   0,   139, 0,   0,   0,   0,   0,   143, 0,   212, 217, 218, 219, 216, 220, 0,
-    214, 211, 209, 203, 204, 0,   200, 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   215,
-    0,   246, 247, 248, 249, 245, 250, 182, 186, 188, 0,   190, 191, 193, 194, 178, 198, 199, 0,
-    252, 189, 251, 0,   0,   253, 0,   254};
+    0,   0,   0,   0,   0,   0,   0,   0,   164, 0,   169, 170, 168, 171, 166, 152, 163, 17,  0,
+    0,   191, 0,   0,   0,   0,   0,   240, 241, 242, 243, 244, 245, 246, 0,   267, 268, 269, 270,
+    271, 272, 273, 274, 275, 192, 193, 0,   195, 196, 197, 0,   199, 0,   0,   0,   0,   204, 0,
+    0,   167, 151, 0,   151, 0,   0,   151, 0,   0,   0,   0,   0,   151, 0,   0,   0,   0,   0,
+    155, 0,   215, 216, 0,   212, 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   258,
+    259, 260, 261, 257, 262, 194, 198, 200, 0,   202, 203, 205, 206, 190, 210, 211, 0,   264, 201,
+    263, 0,   0,   265, 0,   266};
 
 const short PipelineParserGen::yypgoto_[] = {
-    -226, -226, -226, -203, -201, -131, -183, -118, -226, -226, -226, -226, -226, -226, -226, -226,
-    -6,   -226, -5,   -7,   -1,   -226, -226, -225, -36,  -226, -226, -226, -226, -226, -226, -226,
-    -219, -226, -226, -226, -226, 200,  -226, -226, -226, -226, -226, -226, -226, -226, 136,  14,
-    -176, -16,  -124, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226, -226,
-    -226, -226, -226, -226, -226, -221, -117, -226, 54,   -226};
+    -274, -274, -274, -140, -274, -132, -133, -129, -22,  -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -12,  -274, -11,  -13,  -7,   -274, -274, -98,  -146, -274, -274, -274, -274, -274,
+    -274, -274, -20,  -274, -274, -274, -274, 164,  -274, -274, -274, -274, -274, -274, -274, -274,
+    107,  -5,   -225, -135, -224, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274, -274,
+    -274, -274, -274, -274, -274, -274, -274, -273, 110,  -274, -274, 189,  -274, -274, 7,    -274};
 
 const short PipelineParserGen::yydefgoto_[] = {
-    -1,  101, 295, 102, 103, 104, 105, 299, 379, 106, 300, 380, 229, 230, 231, 232, 233, 234,
-    235, 236, 237, 238, 239, 355, 240, 241, 242, 243, 244, 245, 246, 247, 248, 312, 313, 314,
-    354, 4,   12,  13,  14,  15,  16,  17,  18,  41,  123, 33,  249, 250, 255, 125, 126, 213,
-    127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144,
-    145, 405, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161,
-    162, 163, 164, 165, 166, 167, 168, 169, 170, 418, 422, 251, 356, 2,   37,  38};
+    -1,  162, 332, 81,  82,  83,  84,  85,  176, 177, 167, 337, 178, 86,  125, 126, 127, 128, 129,
+    130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 286, 146, 147, 148,
+    157, 10,  18,  19,  20,  21,  22,  23,  24,  152, 194, 100, 287, 288, 293, 196, 197, 285, 198,
+    199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 422,
+    217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235,
+    236, 237, 238, 239, 240, 241, 435, 439, 289, 159, 7,   11,  149, 3,   5,   104, 105};
 
 const short PipelineParserGen::yytable_[] = {
-    31,  29,  30,  31,  29,  30,  32,  109, 23,  32,  296, 122, 297, 269, 270, 271, 272, 273, 274,
-    275, 276, 277, 278, 279, 36,  281, 282, 283, 301, 285, 298, 124, 310, 315, 290, 31,  29,  30,
-    311, 311, 1,   32,  3,   110, 5,   111, 20,  19,  112, 113, 114, 115, 116, 117, 34,  35,  107,
-    261, 262, 263, 264, 265, 266, 267, 39,  122, 40,  42,  43,  21,  22,  23,  24,  44,  108, 172,
-    173, 304, 305, 27,  307, 253, 303, 316, 317, 124, 254, 256, 257, 258, 311, 6,   7,   8,   9,
-    10,  11,  259, 260, 280, 284, 286, 287, 288, 337, 289, 291, 108, 341, 292, 343, 344, 345, 346,
-    302, 348, 349, 306, 118, 350, 119, 120, 121, 318, 21,  22,  23,  24,  351, 352, 370, 353, 372,
-    319, 320, 321, 311, 322, 385, 25,  359, 26,  27,  28,  391, 323, 324, 325, 326, 361, 327, 374,
-    328, 375, 398, 329, 330, 331, 332, 333, 311, 362, 334, 335, 336, 363, 252, 364, 365, 366, 367,
-    377, 368, 369, 338, 339, 340, 342, 347, 417, 383, 357, 110, 108, 111, 384, 358, 21,  22,  23,
-    24,  214, 215, 360, 25,  371, 26,  27,  28,  382, 308, 387, 309, 386, 388, 21,  22,  23,  24,
-    214, 215, 389, 390, 392, 393, 394, 395, 396, 397, 399, 406, 407, 408, 376, 410, 409, 411, 412,
-    413, 414, 415, 416, 419, 421, 424, 425, 378, 171, 381, 45,  0,   420, 268, 0,   0,   423, 108,
-    216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 25,  226, 26,  27,  28,  227, 228, 108, 216,
-    217, 218, 219, 220, 221, 222, 223, 224, 225, 25,  226, 26,  27,  28,  227, 228, 46,  0,   0,
-    47,  0,   0,   0,   0,   0,   0,   48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,
-    60,  61,  62,  63,  64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,
-    79,  80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,  96,  97,
-    98,  99,  100, 0,   0,   0,   0,   0,   0,   404, 0,   0,   0,   0,   0,   0,   0,   0,   0,
+    98,  96,  97,  98,  96,  97,  99,  145, 169, 99,  158, 103, 163, 90,  338, 193, 193, 172, 4,
+    165, 164, 1,   2,   166, 174, 173, 195, 195, 175, 299, 300, 301, 302, 303, 304, 305, 307, 308,
+    309, 310, 311, 312, 313, 314, 315, 316, 317, 6,   319, 320, 321, 8,   323, 9,   25,  87,  101,
+    328, 102, 153, 158, 106, 145, 151, 155, 154, 341, 342, 111, 344, 180, 243, 347, 348, 291, 244,
+    292, 294, 295, 245, 296, 297, 298, 318, 94,  322, 356, 324, 145, 88,  89,  90,  91,  368, 325,
+    326, 327, 372, 329, 374, 375, 376, 377, 330, 379, 380, 339, 381, 340, 398, 343, 400, 349, 350,
+    403, 351, 382, 383, 352, 384, 409, 353, 387, 354, 355, 357, 358, 181, 405, 182, 359, 389, 183,
+    184, 185, 186, 187, 188, 145, 360, 98,  96,  97,  390, 361, 333, 99,  391, 168, 392, 393, 394,
+    395, 334, 396, 397, 335, 145, 362, 92,  363, 93,  94,  95,  364, 365, 366, 367, 107, 434, 108,
+    369, 370, 88,  89,  90,  91,  109, 110, 371, 12,  13,  14,  15,  16,  17,  373, 378, 438, 401,
+    402, 111, 88,  89,  90,  91,  385, 345, 346, 386, 388, 399, 189, 404, 190, 191, 192, 406, 407,
+    437, 408, 410, 411, 440, 181, 412, 182, 423, 413, 88,  89,  90,  91,  109, 110, 414, 415, 416,
+    424, 425, 427, 290, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 92,  122, 93,  94,
+    95,  123, 124, 426, 111, 428, 429, 430, 431, 432, 433, 436, 421, 441, 442, 92,  336, 93,  94,
+    95,  306, 179, 242, 156, 150, 0,   0,   0,   145, 145, 0,   111, 112, 113, 114, 115, 116, 117,
+    118, 119, 120, 121, 92,  122, 93,  94,  95,  123, 124, 26,  0,   0,   27,  0,   0,   0,   0,
+    0,   0,   28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,
+    45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
+    64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,  80,  0,   0,
     0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-    402, 400, 401, 0,   373, 0,   403, 294, 0,   0,   0,   0,   0,   0,   48,  49,  50,  51,  52,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   419, 417, 418, 0,   160, 0,   420,
+    161, 0,   0,   0,   0,   0,   0,   28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,
+    40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,
+    59,  60,  61,  62,  63,  64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,
+    78,  79,  80,  170, 0,   0,   171, 0,   0,   0,   0,   0,   0,   28,  29,  30,  31,  32,  33,
+    34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,
     53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,  64,  65,  66,  67,  68,  69,  70,  71,
-    72,  73,  74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,
-    91,  92,  93,  94,  95,  96,  97,  98,  99,  100, 293, 0,   0,   294, 0,   0,   0,   0,   0,
-    0,   48,  49,  50,  51,  52,  53,  54,  55,  56,  0,   0,   0,   0,   0,   0,   0,   0,   0,
+    72,  73,  74,  75,  76,  77,  78,  79,  80,  331, 0,   0,   171, 0,   0,   0,   0,   0,   0,
+    28,  29,  30,  31,  32,  33,  34,  35,  36,  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
     0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   96,  97,  98,  99,  100, 174, 175, 176,
-    177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195,
-    196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212};
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   76,  77,  78,  79,  80,  246, 247, 248, 249,
+    250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268,
+    269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284};
 
 const short PipelineParserGen::yycheck_[] = {
-    7,   7,   7,   10,  10,  10,  7,   43,  10,  10,  213, 47,  213, 189, 190, 191, 192, 193, 194,
-    195, 196, 197, 198, 199, 10,  201, 202, 203, 249, 205, 213, 47,  257, 258, 210, 42,  42,  42,
-    257, 258, 5,   42,  3,   3,   0,   5,   3,   6,   8,   9,   10,  11,  12,  13,  3,   3,   42,
-    181, 182, 183, 184, 185, 186, 187, 4,   101, 4,   22,  20,  8,   9,   10,  11,  3,   67,  4,
-    21,  253, 254, 81,  256, 5,   4,   259, 260, 101, 5,   5,   5,   5,   309, 14,  15,  16,  17,
-    18,  19,  5,   5,   5,   5,   5,   5,   5,   280, 5,   5,   67,  284, 5,   286, 287, 288, 289,
-    6,   291, 292, 4,   78,  295, 80,  81,  82,  4,   8,   9,   10,  11,  304, 305, 351, 307, 353,
-    4,   4,   4,   355, 4,   359, 78,  316, 80,  81,  82,  365, 4,   4,   62,  4,   325, 4,   354,
-    4,   354, 379, 4,   4,   4,   4,   4,   379, 337, 4,   4,   4,   341, 173, 343, 344, 345, 346,
-    354, 348, 349, 4,   4,   4,   4,   4,   64,  4,   6,   3,   67,  5,   4,   6,   8,   9,   10,
-    11,  12,  13,  6,   78,  6,   80,  81,  82,  6,   3,   63,  5,   4,   6,   8,   9,   10,  11,
-    12,  13,  6,   6,   6,   6,   6,   6,   6,   6,   6,   4,   4,   4,   354, 4,   6,   4,   4,
-    4,   4,   4,   4,   4,   65,  4,   4,   354, 101, 355, 39,  -1,  417, 188, -1,  -1,  421, 67,
-    68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,  67,  68,
-    69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,  4,   -1,  -1,
+    13,  13,  13,  16,  16,  16,  13,  27,  154, 16,  108, 16,  152, 10,  287, 161, 162, 157, 5,
+    152, 152, 85,  86,  152, 157, 157, 161, 162, 157, 253, 254, 255, 256, 257, 258, 259, 261, 262,
+    263, 264, 265, 266, 267, 268, 269, 270, 271, 3,   273, 274, 275, 0,   277, 3,   6,   3,   3,
+    282, 3,   22,  158, 4,   82,  4,   3,   20,  291, 292, 67,  294, 6,   4,   297, 298, 5,   21,
+    5,   5,   5,   177, 5,   5,   5,   5,   81,  5,   62,  5,   108, 8,   9,   10,  11,  318, 5,
+    5,   5,   322, 5,   324, 325, 326, 327, 5,   329, 330, 6,   332, 4,   382, 4,   384, 4,   4,
+    387, 4,   341, 342, 4,   344, 393, 4,   347, 4,   4,   4,   4,   3,   63,  5,   4,   356, 8,
+    9,   10,  11,  12,  13,  158, 4,   153, 153, 153, 368, 4,   285, 153, 372, 153, 374, 375, 376,
+    377, 285, 379, 380, 285, 177, 4,   78,  4,   80,  81,  82,  4,   4,   4,   4,   3,   64,  5,
+    4,   4,   8,   9,   10,  11,  12,  13,  4,   14,  15,  16,  17,  18,  19,  4,   4,   65,  4,
+    4,   67,  8,   9,   10,  11,  6,   295, 296, 6,   6,   6,   78,  4,   80,  81,  82,  6,   6,
+    434, 6,   6,   6,   438, 3,   6,   5,   4,   6,   8,   9,   10,  11,  12,  13,  6,   6,   6,
+    4,   4,   4,   244, 67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,  80,  81,
+    82,  83,  84,  6,   67,  4,   4,   4,   4,   4,   4,   4,   405, 4,   4,   78,  285, 80,  81,
+    82,  260, 158, 162, 106, 82,  -1,  -1,  -1,  295, 296, -1,  67,  68,  69,  70,  71,  72,  73,
+    74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,  4,   -1,  -1,  7,   -1,  -1,  -1,  -1,
+    -1,  -1,  14,  15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,
+    31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,
+    50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,  64,  65,  66,  -1,  -1,
+    -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
+    -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  405, 405, 405, -1,  4,   -1,  405,
     7,   -1,  -1,  -1,  -1,  -1,  -1,  14,  15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,
     26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,
     45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
-    64,  65,  66,  -1,  -1,  -1,  -1,  -1,  -1,  387, -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
-    -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
-    387, 387, 387, -1,  4,   -1,  387, 7,   -1,  -1,  -1,  -1,  -1,  -1,  14,  15,  16,  17,  18,
-    19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,
-    38,  39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,
-    57,  58,  59,  60,  61,  62,  63,  64,  65,  66,  4,   -1,  -1,  7,   -1,  -1,  -1,  -1,  -1,
-    -1,  14,  15,  16,  17,  18,  19,  20,  21,  22,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
+    64,  65,  66,  4,   -1,  -1,  7,   -1,  -1,  -1,  -1,  -1,  -1,  14,  15,  16,  17,  18,  19,
+    20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,
+    39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,
+    58,  59,  60,  61,  62,  63,  64,  65,  66,  4,   -1,  -1,  7,   -1,  -1,  -1,  -1,  -1,  -1,
+    14,  15,  16,  17,  18,  19,  20,  21,  22,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
     -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,
-    -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  62,  63,  64,  65,  66,  23,  24,  25,
-    26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,
-    45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61};
+    -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  -1,  62,  63,  64,  65,  66,  23,  24,  25,  26,
+    27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,
+    46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61};
 
 const unsigned char PipelineParserGen::yystos_[] = {
-    0,   5,   188, 3,   122, 0,   14,  15,  16,  17,  18,  19,  123, 124, 125, 126, 127, 128, 129,
-    6,   3,   8,   9,   10,  11,  78,  80,  81,  82,  101, 103, 104, 105, 132, 3,   3,   132, 189,
-    190, 4,   4,   130, 22,  20,  3,   122, 4,   7,   14,  15,  16,  17,  18,  19,  20,  21,  22,
-    23,  24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,
-    42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,
-    61,  62,  63,  64,  65,  66,  86,  88,  89,  90,  91,  94,  132, 67,  109, 3,   5,   8,   9,
-    10,  11,  12,  13,  78,  80,  81,  82,  109, 131, 134, 136, 137, 139, 140, 141, 142, 143, 144,
-    145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 159, 160, 161, 162, 163, 164,
-    165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183,
-    131, 4,   21,  23,  24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,
-    39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,
-    58,  59,  60,  61,  138, 12,  13,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  79,  83,
-    84,  97,  98,  99,  100, 101, 102, 103, 104, 105, 106, 107, 109, 110, 111, 112, 113, 114, 115,
-    116, 117, 133, 134, 186, 104, 5,   5,   135, 5,   5,   5,   5,   5,   135, 135, 135, 135, 135,
-    135, 135, 189, 133, 133, 133, 133, 133, 133, 133, 133, 133, 133, 133, 5,   133, 133, 133, 5,
-    133, 5,   5,   5,   5,   133, 5,   5,   4,   7,   87,  88,  89,  91,  92,  95,  186, 6,   4,
-    133, 133, 4,   133, 3,   5,   108, 117, 118, 119, 120, 108, 133, 133, 4,   4,   4,   4,   4,
-    4,   4,   62,  4,   4,   4,   4,   4,   4,   4,   4,   4,   4,   4,   133, 4,   4,   4,   133,
-    4,   133, 133, 133, 133, 4,   133, 133, 133, 133, 133, 133, 121, 108, 187, 6,   6,   133, 6,
-    133, 133, 133, 133, 133, 133, 133, 133, 133, 186, 6,   186, 4,   88,  89,  90,  91,  92,  93,
-    96,  187, 6,   4,   4,   186, 4,   63,  6,   6,   6,   186, 6,   6,   6,   6,   6,   6,   108,
-    6,   101, 103, 104, 105, 109, 158, 4,   4,   4,   6,   4,   4,   4,   4,   4,   4,   4,   64,
-    184, 4,   133, 65,  185, 133, 4,   4};
+    0,   85,  86,  195, 5,   196, 3,   192, 0,   3,   126, 193, 14,  15,  16,  17,  18,  19,  127,
+    128, 129, 130, 131, 132, 133, 6,   4,   7,   14,  15,  16,  17,  18,  19,  20,  21,  22,  23,
+    24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,
+    43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,
+    62,  63,  64,  65,  66,  90,  91,  92,  93,  94,  100, 3,   8,   9,   10,  11,  78,  80,  81,
+    82,  105, 107, 108, 109, 136, 3,   3,   136, 197, 198, 4,   3,   5,   12,  13,  67,  68,  69,
+    70,  71,  72,  73,  74,  75,  76,  77,  79,  83,  84,  101, 102, 103, 104, 105, 106, 107, 108,
+    109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 194, 194, 4,
+    134, 22,  20,  3,   126, 125, 112, 191, 4,   7,   88,  90,  92,  93,  94,  97,  136, 113, 4,
+    7,   90,  92,  93,  94,  95,  96,  99,  191, 6,   3,   5,   8,   9,   10,  11,  12,  13,  78,
+    80,  81,  82,  113, 135, 138, 140, 141, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153,
+    154, 155, 156, 157, 158, 159, 160, 161, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173,
+    174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 135, 4,   21,  112, 23,
+    24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,
+    43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,
+    142, 121, 137, 138, 190, 108, 5,   5,   139, 5,   5,   5,   5,   5,   139, 139, 139, 139, 139,
+    139, 139, 197, 137, 137, 137, 137, 137, 137, 137, 137, 137, 137, 137, 5,   137, 137, 137, 5,
+    137, 5,   5,   5,   5,   137, 5,   5,   4,   89,  90,  92,  94,  95,  98,  190, 6,   4,   137,
+    137, 4,   137, 112, 112, 137, 137, 4,   4,   4,   4,   4,   4,   4,   62,  4,   4,   4,   4,
+    4,   4,   4,   4,   4,   4,   4,   137, 4,   4,   4,   137, 4,   137, 137, 137, 137, 4,   137,
+    137, 137, 137, 137, 137, 6,   6,   137, 6,   137, 137, 137, 137, 137, 137, 137, 137, 137, 190,
+    6,   190, 4,   4,   190, 4,   63,  6,   6,   6,   190, 6,   6,   6,   6,   6,   6,   6,   105,
+    107, 108, 109, 113, 162, 4,   4,   4,   6,   4,   4,   4,   4,   4,   4,   4,   64,  188, 4,
+    137, 65,  189, 137, 4,   4};
 
 const unsigned char PipelineParserGen::yyr1_[] = {
-    0,   85,  188, 122, 122, 190, 189, 123, 123, 123, 123, 123, 123, 129, 124, 125, 132, 132, 132,
-    132, 126, 127, 128, 130, 130, 94,  94,  131, 131, 131, 131, 131, 131, 131, 131, 131, 131, 131,
-    131, 86,  86,  86,  86,  91,  88,  88,  88,  88,  88,  88,  89,  89,  89,  89,  89,  89,  89,
-    90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,
-    90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,  90,
-    90,  109, 110, 111, 112, 114, 115, 116, 97,  98,  99,  100, 102, 106, 107, 101, 101, 103, 103,
-    104, 104, 105, 105, 113, 113, 117, 117, 117, 117, 117, 117, 117, 117, 117, 117, 117, 117, 117,
-    117, 117, 117, 117, 117, 117, 186, 186, 133, 133, 135, 134, 134, 134, 134, 134, 134, 134, 136,
-    137, 138, 138, 95,  87,  87,  87,  87,  92,  139, 139, 139, 139, 139, 139, 139, 139, 139, 139,
-    139, 139, 139, 139, 139, 139, 139, 140, 141, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178,
-    179, 180, 181, 182, 183, 142, 142, 142, 143, 144, 145, 146, 146, 147, 148, 108, 108, 118, 118,
-    119, 187, 187, 120, 121, 121, 96,  93,  93,  93,  93,  93,  149, 149, 149, 149, 149, 149, 149,
-    150, 151, 152, 153, 154, 155, 156, 157, 157, 157, 157, 157, 157, 157, 157, 157, 157, 158, 158,
-    158, 158, 158, 184, 184, 185, 185, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168};
+    0,   87,  195, 195, 196, 126, 126, 198, 197, 127, 127, 127, 127, 127, 127, 133, 128, 129, 136,
+    136, 136, 136, 130, 131, 132, 134, 134, 97,  97,  135, 135, 135, 135, 135, 135, 135, 135, 135,
+    135, 135, 135, 88,  88,  88,  88,  192, 193, 193, 100, 100, 194, 91,  91,  91,  91,  94,  90,
+    90,  90,  90,  90,  90,  92,  92,  92,  92,  92,  92,  92,  93,  93,  93,  93,  93,  93,  93,
+    93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,
+    93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  93,  113, 114, 115, 116, 118, 119,
+    120, 101, 102, 103, 104, 106, 110, 111, 105, 105, 107, 107, 108, 108, 109, 109, 117, 117, 121,
+    121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 190,
+    190, 137, 137, 139, 138, 138, 138, 138, 138, 138, 138, 140, 141, 142, 142, 98,  89,  89,  89,
+    89,  95,  143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143, 143,
+    144, 145, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 146, 146,
+    146, 147, 148, 149, 150, 150, 151, 152, 112, 112, 122, 122, 123, 191, 191, 124, 125, 125, 99,
+    96,  96,  96,  96,  96,  153, 153, 153, 153, 153, 153, 153, 154, 155, 156, 157, 158, 159, 160,
+    161, 161, 161, 161, 161, 161, 161, 161, 161, 161, 162, 162, 162, 162, 162, 188, 188, 189, 189,
+    163, 164, 165, 166, 167, 168, 169, 170, 171, 172};
 
 const signed char PipelineParserGen::yyr2_[] = {
-    0, 2, 3, 0, 4, 0, 2, 1, 1, 1, 1, 1, 1, 5, 3,  7, 1, 1, 1, 1, 2, 2, 4, 0, 2, 2, 2, 1, 1, 1,
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 0, 2, 1, 1, 4, 1, 1, 1, 1, 1, 1,
-    1, 3, 3, 0, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 8, 4,
-    4, 4, 7, 4, 4, 4, 7, 4, 7, 8, 7, 7, 4, 7, 7,  1, 1, 1, 8, 8, 6, 1, 1, 6, 6, 1, 1, 1, 1, 3,
-    0, 2, 3, 0, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 4, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1,
-    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 0, 2, 11, 4, 4, 4, 4, 4, 4, 4, 4, 4};
+    0, 2, 2, 2, 3, 0, 4, 0, 2, 1, 1, 1, 1, 1, 1, 5, 3, 7, 1,  1, 1, 1, 2, 2, 4, 0, 2, 2, 2, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 0, 2, 2, 2,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 1, 1,
+    4, 1, 1, 1, 1, 1, 1, 1, 3, 3, 0, 2, 2, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, 1, 1, 1, 8, 4, 4, 4, 7, 4, 4, 4, 7, 4, 7, 8, 7, 7, 4,  7, 7, 1, 1, 1, 8, 8, 6, 1, 1, 6, 6,
+    1, 1, 1, 1, 3, 0, 2, 3, 0, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 4, 4, 4, 4, 4, 4, 4, 1,
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 0, 2, 11, 4, 4, 4, 4, 4, 4, 4, 4, 4};
 
 
 #if YYDEBUG
@@ -4110,10 +4246,13 @@ const char* const PipelineParserGen::yytname_[] = {"\"EOF\"",
                                                    "DECIMAL_NON_ZERO",
                                                    "MIN_KEY",
                                                    "MAX_KEY",
+                                                   "START_PIPELINE",
+                                                   "START_MATCH",
                                                    "$accept",
                                                    "projectionFieldname",
                                                    "expressionFieldname",
                                                    "stageAsUserFieldname",
+                                                   "filterFieldname",
                                                    "argAsUserFieldname",
                                                    "aggExprAsUserFieldname",
                                                    "invariableUserFieldname",
@@ -4122,6 +4261,7 @@ const char* const PipelineParserGen::yytname_[] = {"\"EOF\"",
                                                    "projectField",
                                                    "expressionField",
                                                    "valueField",
+                                                   "filterField",
                                                    "dbPointer",
                                                    "javascript",
                                                    "symbol",
@@ -4213,6 +4353,10 @@ const char* const PipelineParserGen::yytname_[] = {"\"EOF\"",
                                                    "onNullArg",
                                                    "expressions",
                                                    "values",
+                                                   "matchExpression",
+                                                   "filterFields",
+                                                   "filterVal",
+                                                   "start",
                                                    "pipeline",
                                                    "START_ORDERED_OBJECT",
                                                    "$@1",
@@ -4222,23 +4366,24 @@ const char* const PipelineParserGen::yytname_[] = {"\"EOF\"",
 
 #if YYDEBUG
 const short PipelineParserGen::yyrline_[] = {
-    0,    246,  246,  252,  253,  261,  261,  264,  264,  264,  264,  264,  264,  267,  277,  283,
-    293,  293,  293,  293,  297,  302,  307,  313,  316,  323,  326,  332,  333,  336,  339,  342,
-    345,  348,  351,  354,  357,  360,  363,  367,  367,  367,  367,  371,  379,  382,  385,  388,
-    391,  394,  403,  406,  409,  412,  415,  418,  421,  429,  432,  435,  438,  441,  444,  447,
-    450,  453,  456,  459,  462,  465,  468,  471,  474,  477,  480,  483,  486,  489,  492,  495,
-    498,  501,  504,  507,  510,  513,  516,  519,  522,  525,  528,  531,  534,  537,  540,  543,
-    550,  556,  562,  568,  574,  580,  586,  592,  598,  604,  610,  616,  622,  628,  634,  637,
-    643,  646,  652,  655,  661,  664,  670,  673,  679,  680,  681,  682,  683,  684,  685,  686,
-    687,  688,  689,  690,  691,  692,  693,  694,  695,  696,  697,  704,  705,  712,  712,  716,
-    721,  721,  721,  721,  721,  721,  722,  728,  736,  742,  745,  752,  759,  759,  759,  759,
-    763,  769,  769,  769,  769,  769,  769,  769,  769,  769,  769,  769,  769,  769,  770,  770,
-    770,  770,  774,  784,  790,  795,  800,  806,  811,  816,  821,  827,  832,  838,  847,  853,
-    859,  864,  870,  876,  876,  876,  880,  890,  900,  907,  907,  911,  918,  925,  925,  929,
-    929,  933,  939,  940,  947,  953,  956,  963,  970,  971,  972,  973,  974,  977,  977,  977,
-    977,  977,  977,  977,  979,  984,  989,  994,  999,  1004, 1009, 1015, 1016, 1017, 1018, 1019,
-    1020, 1021, 1022, 1023, 1024, 1030, 1030, 1030, 1030, 1030, 1034, 1037, 1044, 1047, 1053, 1062,
-    1067, 1072, 1077, 1082, 1087, 1092, 1097, 1102};
+    0,    248,  248,  249,  256,  262,  263,  271,  271,  274,  274,  274,  274,  274,  274,  277,
+    287,  293,  303,  303,  303,  303,  307,  312,  317,  323,  326,  333,  336,  342,  343,  346,
+    349,  352,  355,  358,  361,  364,  367,  370,  373,  377,  377,  377,  377,  381,  387,  390,
+    397,  400,  406,  410,  410,  410,  410,  414,  422,  425,  428,  431,  434,  437,  446,  449,
+    452,  455,  458,  461,  464,  472,  475,  478,  481,  484,  487,  490,  493,  496,  499,  502,
+    505,  508,  511,  514,  517,  520,  523,  526,  529,  532,  535,  538,  541,  544,  547,  550,
+    553,  556,  559,  562,  565,  568,  571,  574,  577,  580,  583,  586,  593,  599,  605,  611,
+    617,  623,  629,  635,  641,  647,  653,  659,  665,  671,  677,  680,  686,  689,  695,  698,
+    704,  707,  713,  716,  722,  723,  724,  725,  726,  727,  728,  729,  730,  731,  732,  733,
+    734,  735,  736,  737,  738,  739,  740,  747,  748,  755,  755,  759,  764,  764,  764,  764,
+    764,  764,  765,  771,  779,  785,  788,  795,  802,  802,  802,  802,  806,  812,  812,  812,
+    812,  812,  812,  812,  812,  812,  812,  812,  812,  812,  813,  813,  813,  813,  817,  827,
+    833,  838,  843,  849,  854,  859,  864,  870,  875,  881,  890,  896,  902,  907,  913,  919,
+    919,  919,  923,  933,  943,  950,  950,  954,  961,  968,  968,  972,  972,  976,  982,  983,
+    990,  996,  999,  1006, 1013, 1014, 1015, 1016, 1017, 1020, 1020, 1020, 1020, 1020, 1020, 1020,
+    1022, 1027, 1032, 1037, 1042, 1047, 1052, 1058, 1059, 1060, 1061, 1062, 1063, 1064, 1065, 1066,
+    1067, 1073, 1073, 1073, 1073, 1073, 1077, 1080, 1087, 1090, 1096, 1105, 1110, 1115, 1120, 1125,
+    1130, 1135, 1140, 1145};
 
 void PipelineParserGen::yy_stack_print_() const {
     *yycdebug_ << "Stack now";
@@ -4259,8 +4404,8 @@ void PipelineParserGen::yy_reduce_print_(int yyrule) const {
 #endif  // YYDEBUG
 
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 }  // namespace mongo
-#line 4075 "pipeline_parser_gen.cpp"
+#line 4205 "src/mongo/db/cst/pipeline_parser_gen.cpp"
 
-#line 1106 "pipeline_grammar.yy"
+#line 1149 "src/mongo/db/cst/pipeline_grammar.yy"
diff --git a/src/mongo/db/cst/pipeline_parser_gen.hpp b/src/mongo/db/cst/pipeline_parser_gen.hpp
index 806dba9ea30..57385ef3c13 100644
--- a/src/mongo/db/cst/pipeline_parser_gen.hpp
+++ b/src/mongo/db/cst/pipeline_parser_gen.hpp
@@ -1,4 +1,4 @@
-// A Bison parser, made by GNU Bison 3.6.3.
+// A Bison parser, made by GNU Bison 3.6.
 
 // Skeleton interface for Bison LALR(1) parsers in C++
 
@@ -32,7 +32,7 @@
 
 
 /**
- ** \file pipeline_parser_gen.hpp
+ ** \file src/mongo/db/cst/pipeline_parser_gen.hpp
  ** Define the mongo::parser class.
  */
 
@@ -42,10 +42,10 @@
 // especially those whose name start with YY_ or yy_.  They are
 // private implementation details that can be changed or removed.
 
-#ifndef YY_YY_PIPELINE_PARSER_GEN_HPP_INCLUDED
-#define YY_YY_PIPELINE_PARSER_GEN_HPP_INCLUDED
+#ifndef YY_YY_SRC_MONGO_DB_CST_PIPELINE_PARSER_GEN_HPP_INCLUDED
+#define YY_YY_SRC_MONGO_DB_CST_PIPELINE_PARSER_GEN_HPP_INCLUDED
 // "%code requires" blocks.
-#line 66 "pipeline_grammar.yy"
+#line 66 "src/mongo/db/cst/pipeline_grammar.yy"
 
 #include "mongo/db/cst/c_node.h"
 #include "mongo/db/cst/key_fieldname.h"
@@ -61,7 +61,7 @@ class BSONLexer;
 #pragma warning(disable : 4065)
 #endif
 
-#line 65 "pipeline_parser_gen.hpp"
+#line 65 "src/mongo/db/cst/pipeline_parser_gen.hpp"
 
 #include <cassert>
 #include <cstdlib>  // std::abort
@@ -190,9 +190,9 @@ class BSONLexer;
 #define YYDEBUG 0
 #endif
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 namespace mongo {
-#line 200 "pipeline_parser_gen.hpp"
+#line 200 "src/mongo/db/cst/pipeline_parser_gen.hpp"
 
 
 /// A Bison parser.
@@ -472,11 +472,15 @@ public:
             // sqrt
             // subtract
             // trunc
+            // matchExpression
+            // filterFields
+            // filterVal
             char dummy7[sizeof(CNode)];
 
             // projectionFieldname
             // expressionFieldname
             // stageAsUserFieldname
+            // filterFieldname
             // argAsUserFieldname
             // aggExprAsUserFieldname
             // invariableUserFieldname
@@ -520,6 +524,7 @@ public:
             // projectField
             // expressionField
             // valueField
+            // filterField
             // onErrorArg
             // onNullArg
             char dummy20[sizeof(std::pair<CNode::Fieldname, CNode>)];
@@ -654,7 +659,9 @@ public:
             DOUBLE_NON_ZERO = 81,             // DOUBLE_NON_ZERO
             DECIMAL_NON_ZERO = 82,            // DECIMAL_NON_ZERO
             MIN_KEY = 83,                     // MIN_KEY
-            MAX_KEY = 84                      // MAX_KEY
+            MAX_KEY = 84,                     // MAX_KEY
+            START_PIPELINE = 85,              // START_PIPELINE
+            START_MATCH = 86                  // START_MATCH
         };
         /// Backward compatibility alias (Bison 3.6).
         typedef token_kind_type yytokentype;
@@ -669,7 +676,7 @@ public:
     /// Symbol kinds.
     struct symbol_kind {
         enum symbol_kind_type {
-            YYNTOKENS = 85,  ///< Number of tokens.
+            YYNTOKENS = 87,  ///< Number of tokens.
             S_YYEMPTY = -2,
             S_YYEOF = 0,                        // "EOF"
             S_YYerror = 1,                      // error
@@ -756,112 +763,120 @@ public:
             S_DECIMAL_NON_ZERO = 82,            // DECIMAL_NON_ZERO
             S_MIN_KEY = 83,                     // MIN_KEY
             S_MAX_KEY = 84,                     // MAX_KEY
-            S_YYACCEPT = 85,                    // $accept
-            S_projectionFieldname = 86,         // projectionFieldname
-            S_expressionFieldname = 87,         // expressionFieldname
-            S_stageAsUserFieldname = 88,        // stageAsUserFieldname
-            S_argAsUserFieldname = 89,          // argAsUserFieldname
-            S_aggExprAsUserFieldname = 90,      // aggExprAsUserFieldname
-            S_invariableUserFieldname = 91,     // invariableUserFieldname
-            S_idAsUserFieldname = 92,           // idAsUserFieldname
-            S_valueFieldname = 93,              // valueFieldname
-            S_projectField = 94,                // projectField
-            S_expressionField = 95,             // expressionField
-            S_valueField = 96,                  // valueField
-            S_dbPointer = 97,                   // dbPointer
-            S_javascript = 98,                  // javascript
-            S_symbol = 99,                      // symbol
-            S_javascriptWScope = 100,           // javascriptWScope
-            S_int = 101,                        // int
-            S_timestamp = 102,                  // timestamp
-            S_long = 103,                       // long
-            S_double = 104,                     // double
-            S_decimal = 105,                    // decimal
-            S_minKey = 106,                     // minKey
-            S_maxKey = 107,                     // maxKey
-            S_value = 108,                      // value
-            S_string = 109,                     // string
-            S_binary = 110,                     // binary
-            S_undefined = 111,                  // undefined
-            S_objectId = 112,                   // objectId
-            S_bool = 113,                       // bool
-            S_date = 114,                       // date
-            S_null = 115,                       // null
-            S_regex = 116,                      // regex
-            S_simpleValue = 117,                // simpleValue
-            S_compoundValue = 118,              // compoundValue
-            S_valueArray = 119,                 // valueArray
-            S_valueObject = 120,                // valueObject
-            S_valueFields = 121,                // valueFields
-            S_stageList = 122,                  // stageList
-            S_stage = 123,                      // stage
-            S_inhibitOptimization = 124,        // inhibitOptimization
-            S_unionWith = 125,                  // unionWith
-            S_skip = 126,                       // skip
-            S_limit = 127,                      // limit
-            S_project = 128,                    // project
-            S_sample = 129,                     // sample
-            S_projectFields = 130,              // projectFields
-            S_projection = 131,                 // projection
-            S_num = 132,                        // num
-            S_expression = 133,                 // expression
-            S_compoundExpression = 134,         // compoundExpression
-            S_exprFixedTwoArg = 135,            // exprFixedTwoArg
-            S_expressionArray = 136,            // expressionArray
-            S_expressionObject = 137,           // expressionObject
-            S_expressionFields = 138,           // expressionFields
-            S_maths = 139,                      // maths
-            S_add = 140,                        // add
-            S_atan2 = 141,                      // atan2
-            S_boolExps = 142,                   // boolExps
-            S_and = 143,                        // and
-            S_or = 144,                         // or
-            S_not = 145,                        // not
-            S_literalEscapes = 146,             // literalEscapes
-            S_const = 147,                      // const
-            S_literal = 148,                    // literal
-            S_compExprs = 149,                  // compExprs
-            S_cmp = 150,                        // cmp
-            S_eq = 151,                         // eq
-            S_gt = 152,                         // gt
-            S_gte = 153,                        // gte
-            S_lt = 154,                         // lt
-            S_lte = 155,                        // lte
-            S_ne = 156,                         // ne
-            S_typeExpression = 157,             // typeExpression
-            S_typeValue = 158,                  // typeValue
-            S_convert = 159,                    // convert
-            S_toBool = 160,                     // toBool
-            S_toDate = 161,                     // toDate
-            S_toDecimal = 162,                  // toDecimal
-            S_toDouble = 163,                   // toDouble
-            S_toInt = 164,                      // toInt
-            S_toLong = 165,                     // toLong
-            S_toObjectId = 166,                 // toObjectId
-            S_toString = 167,                   // toString
-            S_type = 168,                       // type
-            S_abs = 169,                        // abs
-            S_ceil = 170,                       // ceil
-            S_divide = 171,                     // divide
-            S_exponent = 172,                   // exponent
-            S_floor = 173,                      // floor
-            S_ln = 174,                         // ln
-            S_log = 175,                        // log
-            S_logten = 176,                     // logten
-            S_mod = 177,                        // mod
-            S_multiply = 178,                   // multiply
-            S_pow = 179,                        // pow
-            S_round = 180,                      // round
-            S_sqrt = 181,                       // sqrt
-            S_subtract = 182,                   // subtract
-            S_trunc = 183,                      // trunc
-            S_onErrorArg = 184,                 // onErrorArg
-            S_onNullArg = 185,                  // onNullArg
-            S_expressions = 186,                // expressions
-            S_values = 187,                     // values
-            S_pipeline = 188,                   // pipeline
-            S_START_ORDERED_OBJECT = 189,       // START_ORDERED_OBJECT
-            S_190_1 = 190                       // $@1
+            S_START_PIPELINE = 85,              // START_PIPELINE
+            S_START_MATCH = 86,                 // START_MATCH
+            S_YYACCEPT = 87,                    // $accept
+            S_projectionFieldname = 88,         // projectionFieldname
+            S_expressionFieldname = 89,         // expressionFieldname
+            S_stageAsUserFieldname = 90,        // stageAsUserFieldname
+            S_filterFieldname = 91,             // filterFieldname
+            S_argAsUserFieldname = 92,          // argAsUserFieldname
+            S_aggExprAsUserFieldname = 93,      // aggExprAsUserFieldname
+            S_invariableUserFieldname = 94,     // invariableUserFieldname
+            S_idAsUserFieldname = 95,           // idAsUserFieldname
+            S_valueFieldname = 96,              // valueFieldname
+            S_projectField = 97,                // projectField
+            S_expressionField = 98,             // expressionField
+            S_valueField = 99,                  // valueField
+            S_filterField = 100,                // filterField
+            S_dbPointer = 101,                  // dbPointer
+            S_javascript = 102,                 // javascript
+            S_symbol = 103,                     // symbol
+            S_javascriptWScope = 104,           // javascriptWScope
+            S_int = 105,                        // int
+            S_timestamp = 106,                  // timestamp
+            S_long = 107,                       // long
+            S_double = 108,                     // double
+            S_decimal = 109,                    // decimal
+            S_minKey = 110,                     // minKey
+            S_maxKey = 111,                     // maxKey
+            S_value = 112,                      // value
+            S_string = 113,                     // string
+            S_binary = 114,                     // binary
+            S_undefined = 115,                  // undefined
+            S_objectId = 116,                   // objectId
+            S_bool = 117,                       // bool
+            S_date = 118,                       // date
+            S_null = 119,                       // null
+            S_regex = 120,                      // regex
+            S_simpleValue = 121,                // simpleValue
+            S_compoundValue = 122,              // compoundValue
+            S_valueArray = 123,                 // valueArray
+            S_valueObject = 124,                // valueObject
+            S_valueFields = 125,                // valueFields
+            S_stageList = 126,                  // stageList
+            S_stage = 127,                      // stage
+            S_inhibitOptimization = 128,        // inhibitOptimization
+            S_unionWith = 129,                  // unionWith
+            S_skip = 130,                       // skip
+            S_limit = 131,                      // limit
+            S_project = 132,                    // project
+            S_sample = 133,                     // sample
+            S_projectFields = 134,              // projectFields
+            S_projection = 135,                 // projection
+            S_num = 136,                        // num
+            S_expression = 137,                 // expression
+            S_compoundExpression = 138,         // compoundExpression
+            S_exprFixedTwoArg = 139,            // exprFixedTwoArg
+            S_expressionArray = 140,            // expressionArray
+            S_expressionObject = 141,           // expressionObject
+            S_expressionFields = 142,           // expressionFields
+            S_maths = 143,                      // maths
+            S_add = 144,                        // add
+            S_atan2 = 145,                      // atan2
+            S_boolExps = 146,                   // boolExps
+            S_and = 147,                        // and
+            S_or = 148,                         // or
+            S_not = 149,                        // not
+            S_literalEscapes = 150,             // literalEscapes
+            S_const = 151,                      // const
+            S_literal = 152,                    // literal
+            S_compExprs = 153,                  // compExprs
+            S_cmp = 154,                        // cmp
+            S_eq = 155,                         // eq
+            S_gt = 156,                         // gt
+            S_gte = 157,                        // gte
+            S_lt = 158,                         // lt
+            S_lte = 159,                        // lte
+            S_ne = 160,                         // ne
+            S_typeExpression = 161,             // typeExpression
+            S_typeValue = 162,                  // typeValue
+            S_convert = 163,                    // convert
+            S_toBool = 164,                     // toBool
+            S_toDate = 165,                     // toDate
+            S_toDecimal = 166,                  // toDecimal
+            S_toDouble = 167,                   // toDouble
+            S_toInt = 168,                      // toInt
+            S_toLong = 169,                     // toLong
+            S_toObjectId = 170,                 // toObjectId
+            S_toString = 171,                   // toString
+            S_type = 172,                       // type
+            S_abs = 173,                        // abs
+            S_ceil = 174,                       // ceil
+            S_divide = 175,                     // divide
+            S_exponent = 176,                   // exponent
+            S_floor = 177,                      // floor
+            S_ln = 178,                         // ln
+            S_log = 179,                        // log
+            S_logten = 180,                     // logten
+            S_mod = 181,                        // mod
+            S_multiply = 182,                   // multiply
+            S_pow = 183,                        // pow
+            S_round = 184,                      // round
+            S_sqrt = 185,                       // sqrt
+            S_subtract = 186,                   // subtract
+            S_trunc = 187,                      // trunc
+            S_onErrorArg = 188,                 // onErrorArg
+            S_onNullArg = 189,                  // onNullArg
+            S_expressions = 190,                // expressions
+            S_values = 191,                     // values
+            S_matchExpression = 192,            // matchExpression
+            S_filterFields = 193,               // filterFields
+            S_filterVal = 194,                  // filterVal
+            S_start = 195,                      // start
+            S_pipeline = 196,                   // pipeline
+            S_START_ORDERED_OBJECT = 197,       // START_ORDERED_OBJECT
+            S_198_1 = 198                       // $@1
         };
     };
 
@@ -914,104 +929,108 @@ public:
                     value.move<BSONSymbol>(std::move(that.value));
                     break;
 
-                case 97:   // dbPointer
-                case 98:   // javascript
-                case 99:   // symbol
-                case 100:  // javascriptWScope
-                case 101:  // int
-                case 102:  // timestamp
-                case 103:  // long
-                case 104:  // double
-                case 105:  // decimal
-                case 106:  // minKey
-                case 107:  // maxKey
-                case 108:  // value
-                case 109:  // string
-                case 110:  // binary
-                case 111:  // undefined
-                case 112:  // objectId
-                case 113:  // bool
-                case 114:  // date
-                case 115:  // null
-                case 116:  // regex
-                case 117:  // simpleValue
-                case 118:  // compoundValue
-                case 119:  // valueArray
-                case 120:  // valueObject
-                case 121:  // valueFields
-                case 122:  // stageList
-                case 123:  // stage
-                case 124:  // inhibitOptimization
-                case 125:  // unionWith
-                case 126:  // skip
-                case 127:  // limit
-                case 128:  // project
-                case 129:  // sample
-                case 130:  // projectFields
-                case 131:  // projection
-                case 132:  // num
-                case 133:  // expression
-                case 134:  // compoundExpression
-                case 135:  // exprFixedTwoArg
-                case 136:  // expressionArray
-                case 137:  // expressionObject
-                case 138:  // expressionFields
-                case 139:  // maths
-                case 140:  // add
-                case 141:  // atan2
-                case 142:  // boolExps
-                case 143:  // and
-                case 144:  // or
-                case 145:  // not
-                case 146:  // literalEscapes
-                case 147:  // const
-                case 148:  // literal
-                case 149:  // compExprs
-                case 150:  // cmp
-                case 151:  // eq
-                case 152:  // gt
-                case 153:  // gte
-                case 154:  // lt
-                case 155:  // lte
-                case 156:  // ne
-                case 157:  // typeExpression
-                case 158:  // typeValue
-                case 159:  // convert
-                case 160:  // toBool
-                case 161:  // toDate
-                case 162:  // toDecimal
-                case 163:  // toDouble
-                case 164:  // toInt
-                case 165:  // toLong
-                case 166:  // toObjectId
-                case 167:  // toString
-                case 168:  // type
-                case 169:  // abs
-                case 170:  // ceil
-                case 171:  // divide
-                case 172:  // exponent
-                case 173:  // floor
-                case 174:  // ln
-                case 175:  // log
-                case 176:  // logten
-                case 177:  // mod
-                case 178:  // multiply
-                case 179:  // pow
-                case 180:  // round
-                case 181:  // sqrt
-                case 182:  // subtract
-                case 183:  // trunc
+                case 101:  // dbPointer
+                case 102:  // javascript
+                case 103:  // symbol
+                case 104:  // javascriptWScope
+                case 105:  // int
+                case 106:  // timestamp
+                case 107:  // long
+                case 108:  // double
+                case 109:  // decimal
+                case 110:  // minKey
+                case 111:  // maxKey
+                case 112:  // value
+                case 113:  // string
+                case 114:  // binary
+                case 115:  // undefined
+                case 116:  // objectId
+                case 117:  // bool
+                case 118:  // date
+                case 119:  // null
+                case 120:  // regex
+                case 121:  // simpleValue
+                case 122:  // compoundValue
+                case 123:  // valueArray
+                case 124:  // valueObject
+                case 125:  // valueFields
+                case 126:  // stageList
+                case 127:  // stage
+                case 128:  // inhibitOptimization
+                case 129:  // unionWith
+                case 130:  // skip
+                case 131:  // limit
+                case 132:  // project
+                case 133:  // sample
+                case 134:  // projectFields
+                case 135:  // projection
+                case 136:  // num
+                case 137:  // expression
+                case 138:  // compoundExpression
+                case 139:  // exprFixedTwoArg
+                case 140:  // expressionArray
+                case 141:  // expressionObject
+                case 142:  // expressionFields
+                case 143:  // maths
+                case 144:  // add
+                case 145:  // atan2
+                case 146:  // boolExps
+                case 147:  // and
+                case 148:  // or
+                case 149:  // not
+                case 150:  // literalEscapes
+                case 151:  // const
+                case 152:  // literal
+                case 153:  // compExprs
+                case 154:  // cmp
+                case 155:  // eq
+                case 156:  // gt
+                case 157:  // gte
+                case 158:  // lt
+                case 159:  // lte
+                case 160:  // ne
+                case 161:  // typeExpression
+                case 162:  // typeValue
+                case 163:  // convert
+                case 164:  // toBool
+                case 165:  // toDate
+                case 166:  // toDecimal
+                case 167:  // toDouble
+                case 168:  // toInt
+                case 169:  // toLong
+                case 170:  // toObjectId
+                case 171:  // toString
+                case 172:  // type
+                case 173:  // abs
+                case 174:  // ceil
+                case 175:  // divide
+                case 176:  // exponent
+                case 177:  // floor
+                case 178:  // ln
+                case 179:  // log
+                case 180:  // logten
+                case 181:  // mod
+                case 182:  // multiply
+                case 183:  // pow
+                case 184:  // round
+                case 185:  // sqrt
+                case 186:  // subtract
+                case 187:  // trunc
+                case 192:  // matchExpression
+                case 193:  // filterFields
+                case 194:  // filterVal
                     value.move<CNode>(std::move(that.value));
                     break;
 
-                case 86:  // projectionFieldname
-                case 87:  // expressionFieldname
-                case 88:  // stageAsUserFieldname
-                case 89:  // argAsUserFieldname
-                case 90:  // aggExprAsUserFieldname
-                case 91:  // invariableUserFieldname
-                case 92:  // idAsUserFieldname
-                case 93:  // valueFieldname
+                case 88:  // projectionFieldname
+                case 89:  // expressionFieldname
+                case 90:  // stageAsUserFieldname
+                case 91:  // filterFieldname
+                case 92:  // argAsUserFieldname
+                case 93:  // aggExprAsUserFieldname
+                case 94:  // invariableUserFieldname
+                case 95:  // idAsUserFieldname
+                case 96:  // valueFieldname
                     value.move<CNode::Fieldname>(std::move(that.value));
                     break;
 
@@ -1059,11 +1078,12 @@ public:
                     value.move<long long>(std::move(that.value));
                     break;
 
-                case 94:   // projectField
-                case 95:   // expressionField
-                case 96:   // valueField
-                case 184:  // onErrorArg
-                case 185:  // onNullArg
+                case 97:   // projectField
+                case 98:   // expressionField
+                case 99:   // valueField
+                case 100:  // filterField
+                case 188:  // onErrorArg
+                case 189:  // onNullArg
                     value.move<std::pair<CNode::Fieldname, CNode>>(std::move(that.value));
                     break;
 
@@ -1072,8 +1092,8 @@ public:
                     value.move<std::string>(std::move(that.value));
                     break;
 
-                case 186:  // expressions
-                case 187:  // values
+                case 190:  // expressions
+                case 191:  // values
                     value.move<std::vector<CNode>>(std::move(that.value));
                     break;
 
@@ -1296,104 +1316,108 @@ public:
                     value.template destroy<BSONSymbol>();
                     break;
 
-                case 97:   // dbPointer
-                case 98:   // javascript
-                case 99:   // symbol
-                case 100:  // javascriptWScope
-                case 101:  // int
-                case 102:  // timestamp
-                case 103:  // long
-                case 104:  // double
-                case 105:  // decimal
-                case 106:  // minKey
-                case 107:  // maxKey
-                case 108:  // value
-                case 109:  // string
-                case 110:  // binary
-                case 111:  // undefined
-                case 112:  // objectId
-                case 113:  // bool
-                case 114:  // date
-                case 115:  // null
-                case 116:  // regex
-                case 117:  // simpleValue
-                case 118:  // compoundValue
-                case 119:  // valueArray
-                case 120:  // valueObject
-                case 121:  // valueFields
-                case 122:  // stageList
-                case 123:  // stage
-                case 124:  // inhibitOptimization
-                case 125:  // unionWith
-                case 126:  // skip
-                case 127:  // limit
-                case 128:  // project
-                case 129:  // sample
-                case 130:  // projectFields
-                case 131:  // projection
-                case 132:  // num
-                case 133:  // expression
-                case 134:  // compoundExpression
-                case 135:  // exprFixedTwoArg
-                case 136:  // expressionArray
-                case 137:  // expressionObject
-                case 138:  // expressionFields
-                case 139:  // maths
-                case 140:  // add
-                case 141:  // atan2
-                case 142:  // boolExps
-                case 143:  // and
-                case 144:  // or
-                case 145:  // not
-                case 146:  // literalEscapes
-                case 147:  // const
-                case 148:  // literal
-                case 149:  // compExprs
-                case 150:  // cmp
-                case 151:  // eq
-                case 152:  // gt
-                case 153:  // gte
-                case 154:  // lt
-                case 155:  // lte
-                case 156:  // ne
-                case 157:  // typeExpression
-                case 158:  // typeValue
-                case 159:  // convert
-                case 160:  // toBool
-                case 161:  // toDate
-                case 162:  // toDecimal
-                case 163:  // toDouble
-                case 164:  // toInt
-                case 165:  // toLong
-                case 166:  // toObjectId
-                case 167:  // toString
-                case 168:  // type
-                case 169:  // abs
-                case 170:  // ceil
-                case 171:  // divide
-                case 172:  // exponent
-                case 173:  // floor
-                case 174:  // ln
-                case 175:  // log
-                case 176:  // logten
-                case 177:  // mod
-                case 178:  // multiply
-                case 179:  // pow
-                case 180:  // round
-                case 181:  // sqrt
-                case 182:  // subtract
-                case 183:  // trunc
+                case 101:  // dbPointer
+                case 102:  // javascript
+                case 103:  // symbol
+                case 104:  // javascriptWScope
+                case 105:  // int
+                case 106:  // timestamp
+                case 107:  // long
+                case 108:  // double
+                case 109:  // decimal
+                case 110:  // minKey
+                case 111:  // maxKey
+                case 112:  // value
+                case 113:  // string
+                case 114:  // binary
+                case 115:  // undefined
+                case 116:  // objectId
+                case 117:  // bool
+                case 118:  // date
+                case 119:  // null
+                case 120:  // regex
+                case 121:  // simpleValue
+                case 122:  // compoundValue
+                case 123:  // valueArray
+                case 124:  // valueObject
+                case 125:  // valueFields
+                case 126:  // stageList
+                case 127:  // stage
+                case 128:  // inhibitOptimization
+                case 129:  // unionWith
+                case 130:  // skip
+                case 131:  // limit
+                case 132:  // project
+                case 133:  // sample
+                case 134:  // projectFields
+                case 135:  // projection
+                case 136:  // num
+                case 137:  // expression
+                case 138:  // compoundExpression
+                case 139:  // exprFixedTwoArg
+                case 140:  // expressionArray
+                case 141:  // expressionObject
+                case 142:  // expressionFields
+                case 143:  // maths
+                case 144:  // add
+                case 145:  // atan2
+                case 146:  // boolExps
+                case 147:  // and
+                case 148:  // or
+                case 149:  // not
+                case 150:  // literalEscapes
+                case 151:  // const
+                case 152:  // literal
+                case 153:  // compExprs
+                case 154:  // cmp
+                case 155:  // eq
+                case 156:  // gt
+                case 157:  // gte
+                case 158:  // lt
+                case 159:  // lte
+                case 160:  // ne
+                case 161:  // typeExpression
+                case 162:  // typeValue
+                case 163:  // convert
+                case 164:  // toBool
+                case 165:  // toDate
+                case 166:  // toDecimal
+                case 167:  // toDouble
+                case 168:  // toInt
+                case 169:  // toLong
+                case 170:  // toObjectId
+                case 171:  // toString
+                case 172:  // type
+                case 173:  // abs
+                case 174:  // ceil
+                case 175:  // divide
+                case 176:  // exponent
+                case 177:  // floor
+                case 178:  // ln
+                case 179:  // log
+                case 180:  // logten
+                case 181:  // mod
+                case 182:  // multiply
+                case 183:  // pow
+                case 184:  // round
+                case 185:  // sqrt
+                case 186:  // subtract
+                case 187:  // trunc
+                case 192:  // matchExpression
+                case 193:  // filterFields
+                case 194:  // filterVal
                     value.template destroy<CNode>();
                     break;
 
-                case 86:  // projectionFieldname
-                case 87:  // expressionFieldname
-                case 88:  // stageAsUserFieldname
-                case 89:  // argAsUserFieldname
-                case 90:  // aggExprAsUserFieldname
-                case 91:  // invariableUserFieldname
-                case 92:  // idAsUserFieldname
-                case 93:  // valueFieldname
+                case 88:  // projectionFieldname
+                case 89:  // expressionFieldname
+                case 90:  // stageAsUserFieldname
+                case 91:  // filterFieldname
+                case 92:  // argAsUserFieldname
+                case 93:  // aggExprAsUserFieldname
+                case 94:  // invariableUserFieldname
+                case 95:  // idAsUserFieldname
+                case 96:  // valueFieldname
                     value.template destroy<CNode::Fieldname>();
                     break;
 
@@ -1441,11 +1465,12 @@ public:
                     value.template destroy<long long>();
                     break;
 
-                case 94:   // projectField
-                case 95:   // expressionField
-                case 96:   // valueField
-                case 184:  // onErrorArg
-                case 185:  // onNullArg
+                case 97:   // projectField
+                case 98:   // expressionField
+                case 99:   // valueField
+                case 100:  // filterField
+                case 188:  // onErrorArg
+                case 189:  // onNullArg
                     value.template destroy<std::pair<CNode::Fieldname, CNode>>();
                     break;
 
@@ -1454,8 +1479,8 @@ public:
                     value.template destroy<std::string>();
                     break;
 
-                case 186:  // expressions
-                case 187:  // values
+                case 190:  // expressions
+                case 191:  // values
                     value.template destroy<std::vector<CNode>>();
                     break;
 
@@ -1466,14 +1491,6 @@ public:
             Base::clear();
         }
 
-#if YYDEBUG || 0
-        /// The user-facing name of this symbol.
-        const char* name() const YY_NOEXCEPT {
-            return PipelineParserGen::symbol_name(this->kind());
-        }
-#endif  // #if YYDEBUG || 0
-
-
         /// Backward compatibility (Bison 3.6).
         symbol_kind_type type_get() const YY_NOEXCEPT;
 
@@ -1570,7 +1587,8 @@ public:
                 tok == token::MOD || tok == token::MULTIPLY || tok == token::POW ||
                 tok == token::ROUND || tok == token::SQRT || tok == token::SUBTRACT ||
                 tok == token::TRUNC || tok == token::INPUT_ARG || tok == token::TO_ARG ||
-                tok == token::ON_ERROR_ARG || tok == token::ON_NULL_ARG);
+                tok == token::ON_ERROR_ARG || tok == token::ON_NULL_ARG ||
+                tok == token::START_PIPELINE || tok == token::START_MATCH);
         }
 #else
         symbol_type(int tok, const location_type& l) : super_type(token_type(tok), l) {
@@ -1597,7 +1615,8 @@ public:
                 tok == token::MOD || tok == token::MULTIPLY || tok == token::POW ||
                 tok == token::ROUND || tok == token::SQRT || tok == token::SUBTRACT ||
                 tok == token::TRUNC || tok == token::INPUT_ARG || tok == token::TO_ARG ||
-                tok == token::ON_ERROR_ARG || tok == token::ON_NULL_ARG);
+                tok == token::ON_ERROR_ARG || tok == token::ON_NULL_ARG ||
+                tok == token::START_PIPELINE || tok == token::START_MATCH);
         }
 #endif
 #if 201103L <= YY_CPLUSPLUS
@@ -1841,13 +1860,6 @@ public:
     /// Report a syntax error.
     void error(const syntax_error& err);
 
-#if YYDEBUG || 0
-    /// The user-facing name of the symbol whose (internal) number is
-    /// YYSYMBOL.  No bounds checking.
-    static const char* symbol_name(symbol_kind_type yysymbol);
-#endif  // #if YYDEBUG || 0
-
-
     // Implementation of make_symbol for each symbol type.
 #if 201103L <= YY_CPLUSPLUS
     static symbol_type make_END_OF_FILE(location_type l) {
@@ -2614,6 +2626,24 @@ public:
         return symbol_type(token::MAX_KEY, v, l);
     }
 #endif
+#if 201103L <= YY_CPLUSPLUS
+    static symbol_type make_START_PIPELINE(location_type l) {
+        return symbol_type(token::START_PIPELINE, std::move(l));
+    }
+#else
+    static symbol_type make_START_PIPELINE(const location_type& l) {
+        return symbol_type(token::START_PIPELINE, l);
+    }
+#endif
+#if 201103L <= YY_CPLUSPLUS
+    static symbol_type make_START_MATCH(location_type l) {
+        return symbol_type(token::START_MATCH, std::move(l));
+    }
+#else
+    static symbol_type make_START_MATCH(const location_type& l) {
+        return symbol_type(token::START_MATCH, l);
+    }
+#endif
 
 
 private:
@@ -2650,6 +2680,10 @@ private:
     static symbol_kind_type yytranslate_(int t);
 
 #if YYDEBUG || 0
+    /// The user-facing name of the symbol whose (internal) number is
+    /// YYSYMBOL.  No bounds checking.
+    static const char* symbol_name(symbol_kind_type yysymbol);
+
     /// For a symbol, its name in clear.
     static const char* const yytname_[];
 #endif  // #if YYDEBUG || 0
@@ -2890,9 +2924,9 @@ private:
 
     /// Constants.
     enum {
-        yylast_ = 548,  ///< Last index in yytable_.
-        yynnts_ = 106,  ///< Number of nonterminal symbols.
-        yyfinal_ = 5    ///< Termination state number.
+        yylast_ = 623,  ///< Last index in yytable_.
+        yynnts_ = 112,  ///< Number of nonterminal symbols.
+        yyfinal_ = 8    ///< Termination state number.
     };
 
 
@@ -2934,104 +2968,108 @@ PipelineParserGen::basic_symbol<Base>::basic_symbol(const basic_symbol& that)
             value.copy<BSONSymbol>(YY_MOVE(that.value));
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.copy<CNode>(YY_MOVE(that.value));
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.copy<CNode::Fieldname>(YY_MOVE(that.value));
             break;
 
@@ -3079,11 +3117,12 @@ PipelineParserGen::basic_symbol<Base>::basic_symbol(const basic_symbol& that)
             value.copy<long long>(YY_MOVE(that.value));
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.copy<std::pair<CNode::Fieldname, CNode>>(YY_MOVE(that.value));
             break;
 
@@ -3092,8 +3131,8 @@ PipelineParserGen::basic_symbol<Base>::basic_symbol(const basic_symbol& that)
             value.copy<std::string>(YY_MOVE(that.value));
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.copy<std::vector<CNode>>(YY_MOVE(that.value));
             break;
 
@@ -3142,104 +3181,108 @@ void PipelineParserGen::basic_symbol<Base>::move(basic_symbol& s) {
             value.move<BSONSymbol>(YY_MOVE(s.value));
             break;
 
-        case 97:   // dbPointer
-        case 98:   // javascript
-        case 99:   // symbol
-        case 100:  // javascriptWScope
-        case 101:  // int
-        case 102:  // timestamp
-        case 103:  // long
-        case 104:  // double
-        case 105:  // decimal
-        case 106:  // minKey
-        case 107:  // maxKey
-        case 108:  // value
-        case 109:  // string
-        case 110:  // binary
-        case 111:  // undefined
-        case 112:  // objectId
-        case 113:  // bool
-        case 114:  // date
-        case 115:  // null
-        case 116:  // regex
-        case 117:  // simpleValue
-        case 118:  // compoundValue
-        case 119:  // valueArray
-        case 120:  // valueObject
-        case 121:  // valueFields
-        case 122:  // stageList
-        case 123:  // stage
-        case 124:  // inhibitOptimization
-        case 125:  // unionWith
-        case 126:  // skip
-        case 127:  // limit
-        case 128:  // project
-        case 129:  // sample
-        case 130:  // projectFields
-        case 131:  // projection
-        case 132:  // num
-        case 133:  // expression
-        case 134:  // compoundExpression
-        case 135:  // exprFixedTwoArg
-        case 136:  // expressionArray
-        case 137:  // expressionObject
-        case 138:  // expressionFields
-        case 139:  // maths
-        case 140:  // add
-        case 141:  // atan2
-        case 142:  // boolExps
-        case 143:  // and
-        case 144:  // or
-        case 145:  // not
-        case 146:  // literalEscapes
-        case 147:  // const
-        case 148:  // literal
-        case 149:  // compExprs
-        case 150:  // cmp
-        case 151:  // eq
-        case 152:  // gt
-        case 153:  // gte
-        case 154:  // lt
-        case 155:  // lte
-        case 156:  // ne
-        case 157:  // typeExpression
-        case 158:  // typeValue
-        case 159:  // convert
-        case 160:  // toBool
-        case 161:  // toDate
-        case 162:  // toDecimal
-        case 163:  // toDouble
-        case 164:  // toInt
-        case 165:  // toLong
-        case 166:  // toObjectId
-        case 167:  // toString
-        case 168:  // type
-        case 169:  // abs
-        case 170:  // ceil
-        case 171:  // divide
-        case 172:  // exponent
-        case 173:  // floor
-        case 174:  // ln
-        case 175:  // log
-        case 176:  // logten
-        case 177:  // mod
-        case 178:  // multiply
-        case 179:  // pow
-        case 180:  // round
-        case 181:  // sqrt
-        case 182:  // subtract
-        case 183:  // trunc
+        case 101:  // dbPointer
+        case 102:  // javascript
+        case 103:  // symbol
+        case 104:  // javascriptWScope
+        case 105:  // int
+        case 106:  // timestamp
+        case 107:  // long
+        case 108:  // double
+        case 109:  // decimal
+        case 110:  // minKey
+        case 111:  // maxKey
+        case 112:  // value
+        case 113:  // string
+        case 114:  // binary
+        case 115:  // undefined
+        case 116:  // objectId
+        case 117:  // bool
+        case 118:  // date
+        case 119:  // null
+        case 120:  // regex
+        case 121:  // simpleValue
+        case 122:  // compoundValue
+        case 123:  // valueArray
+        case 124:  // valueObject
+        case 125:  // valueFields
+        case 126:  // stageList
+        case 127:  // stage
+        case 128:  // inhibitOptimization
+        case 129:  // unionWith
+        case 130:  // skip
+        case 131:  // limit
+        case 132:  // project
+        case 133:  // sample
+        case 134:  // projectFields
+        case 135:  // projection
+        case 136:  // num
+        case 137:  // expression
+        case 138:  // compoundExpression
+        case 139:  // exprFixedTwoArg
+        case 140:  // expressionArray
+        case 141:  // expressionObject
+        case 142:  // expressionFields
+        case 143:  // maths
+        case 144:  // add
+        case 145:  // atan2
+        case 146:  // boolExps
+        case 147:  // and
+        case 148:  // or
+        case 149:  // not
+        case 150:  // literalEscapes
+        case 151:  // const
+        case 152:  // literal
+        case 153:  // compExprs
+        case 154:  // cmp
+        case 155:  // eq
+        case 156:  // gt
+        case 157:  // gte
+        case 158:  // lt
+        case 159:  // lte
+        case 160:  // ne
+        case 161:  // typeExpression
+        case 162:  // typeValue
+        case 163:  // convert
+        case 164:  // toBool
+        case 165:  // toDate
+        case 166:  // toDecimal
+        case 167:  // toDouble
+        case 168:  // toInt
+        case 169:  // toLong
+        case 170:  // toObjectId
+        case 171:  // toString
+        case 172:  // type
+        case 173:  // abs
+        case 174:  // ceil
+        case 175:  // divide
+        case 176:  // exponent
+        case 177:  // floor
+        case 178:  // ln
+        case 179:  // log
+        case 180:  // logten
+        case 181:  // mod
+        case 182:  // multiply
+        case 183:  // pow
+        case 184:  // round
+        case 185:  // sqrt
+        case 186:  // subtract
+        case 187:  // trunc
+        case 192:  // matchExpression
+        case 193:  // filterFields
+        case 194:  // filterVal
             value.move<CNode>(YY_MOVE(s.value));
             break;
 
-        case 86:  // projectionFieldname
-        case 87:  // expressionFieldname
-        case 88:  // stageAsUserFieldname
-        case 89:  // argAsUserFieldname
-        case 90:  // aggExprAsUserFieldname
-        case 91:  // invariableUserFieldname
-        case 92:  // idAsUserFieldname
-        case 93:  // valueFieldname
+        case 88:  // projectionFieldname
+        case 89:  // expressionFieldname
+        case 90:  // stageAsUserFieldname
+        case 91:  // filterFieldname
+        case 92:  // argAsUserFieldname
+        case 93:  // aggExprAsUserFieldname
+        case 94:  // invariableUserFieldname
+        case 95:  // idAsUserFieldname
+        case 96:  // valueFieldname
             value.move<CNode::Fieldname>(YY_MOVE(s.value));
             break;
 
@@ -3287,11 +3330,12 @@ void PipelineParserGen::basic_symbol<Base>::move(basic_symbol& s) {
             value.move<long long>(YY_MOVE(s.value));
             break;
 
-        case 94:   // projectField
-        case 95:   // expressionField
-        case 96:   // valueField
-        case 184:  // onErrorArg
-        case 185:  // onNullArg
+        case 97:   // projectField
+        case 98:   // expressionField
+        case 99:   // valueField
+        case 100:  // filterField
+        case 188:  // onErrorArg
+        case 189:  // onNullArg
             value.move<std::pair<CNode::Fieldname, CNode>>(YY_MOVE(s.value));
             break;
 
@@ -3300,8 +3344,8 @@ void PipelineParserGen::basic_symbol<Base>::move(basic_symbol& s) {
             value.move<std::string>(YY_MOVE(s.value));
             break;
 
-        case 186:  // expressions
-        case 187:  // values
+        case 190:  // expressions
+        case 191:  // values
             value.move<std::vector<CNode>>(YY_MOVE(s.value));
             break;
 
@@ -3343,9 +3387,9 @@ inline PipelineParserGen::symbol_kind_type PipelineParserGen::by_kind::type_get(
     return this->kind();
 }
 
-#line 58 "pipeline_grammar.yy"
+#line 58 "src/mongo/db/cst/pipeline_grammar.yy"
 }  // namespace mongo
-#line 4121 "pipeline_parser_gen.hpp"
+#line 4173 "src/mongo/db/cst/pipeline_parser_gen.hpp"
 
 
-#endif  // !YY_YY_PIPELINE_PARSER_GEN_HPP_INCLUDED
+#endif  // !YY_YY_SRC_MONGO_DB_CST_PIPELINE_PARSER_GEN_HPP_INCLUDED