Move BSON hashing functionality into BSONObj and BSONElement

1 files changed, 9 insertions, 0 deletions

diff --git a/src/mongo/bson/bsonelement.h b/src/mongo/bson/bsonelement.h
index 67b345545ba..a5937349399 100644
--- a/src/mongo/bson/bsonelement.h
+++ b/src/mongo/bson/bsonelement.h
@@ -400,6 +400,15 @@ namespace mongo {
         */
         int woCompare( const BSONElement &e, bool considerFieldName = true ) const;
 
+        /**
+         * Functor compatible with std::hash for std::unordered_{map,set}
+         * Warning: The hash function is subject to change. Do not use in cases where hashes need
+         *          to be consistent across versions.
+         */
+        struct Hasher {
+            size_t operator() (const BSONElement& elem) const;
+        };
+
         const char * rawdata() const { return data; }
 
         /** 0 == Equality, just not defined yet */