diff options
Diffstat (limited to 'src/mongo/db/matcher/expression_algo.h')
| -rw-r--r-- | src/mongo/db/matcher/expression_algo.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/src/mongo/db/matcher/expression_algo.h b/src/mongo/db/matcher/expression_algo.h index 1144715c8cf..70092eb644c 100644 --- a/src/mongo/db/matcher/expression_algo.h +++ b/src/mongo/db/matcher/expression_algo.h @@ -35,6 +35,7 @@ #include "mongo/base/string_data.h" #include "mongo/stdx/functional.h" +#include "mongo/util/string_map.h" namespace mongo { @@ -114,10 +115,18 @@ void mapOver(MatchExpression* expr, NodeTraversalFunc func, std::string path = " * independent, returns {exprLeft, exprRight}, where each new MatchExpression contains a portion of * 'expr'. * + * Any paths which should be renamed are encoded in 'renames', which maps from path names in 'expr' + * to the new values of those paths. If the return value is {exprLeft, exprRight} or {exprLeft, + * nullptr}, exprLeft will reflect the path renames. For example, suppose the original match + * expression is {old: {$gt: 3}} and 'renames' contains the mapping "old" => "new". The returned + * exprLeft value will be {new: {$gt: 3}}, provided that "old" is not in 'fields'. + * * Never returns {nullptr, nullptr}. */ std::pair<std::unique_ptr<MatchExpression>, std::unique_ptr<MatchExpression>> -splitMatchExpressionBy(std::unique_ptr<MatchExpression> expr, const std::set<std::string>& fields); +splitMatchExpressionBy(std::unique_ptr<MatchExpression> expr, + const std::set<std::string>& fields, + const StringMap<std::string>& renames); } // namespace expression } // namespace mongo |