1 files changed, 11 insertions, 1 deletions
diff --git a/src/mongo/db/matcher/schema/expression_internal_schema_match_array_index.h b/src/mongo/db/matcher/schema/expression_internal_schema_match_array_index.h
index a6c063f9244..05519e17ff3 100644
--- a/src/mongo/db/matcher/schema/expression_internal_schema_match_array_index.h
+++ b/src/mongo/db/matcher/schema/expression_internal_schema_match_array_index.h
@@ -45,7 +45,10 @@ public:
     static constexpr StringData kName = "$_internalSchemaMatchArrayIndex"_sd;
 
     InternalSchemaMatchArrayIndexMatchExpression(
-        StringData path, long long index, std::unique_ptr<ExpressionWithPlaceholder> expression);
+        StringData path,
+        long long index,
+        std::unique_ptr<ExpressionWithPlaceholder> expression,
+        clonable_ptr<ErrorAnnotation> annotation = nullptr);
 
     void debugString(StringBuilder& debug, int indentationLevel) const final;
 
@@ -94,6 +97,13 @@ public:
         visitor->visit(this);
     }
 
+    /**
+     * Returns an index of an array element this expression applies to.
+     */
+    long long arrayIndex() const {
+        return _index;
+    }
+
 private:
     ExpressionOptimizerFunc getOptimizer() const final;