SERVER-6908 Don't pass strings by value

Change lots of code to take <string> arguments by const ref instead
of by value; minor changes to surrounding code.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/mongo/db/queryoptimizer.h b/src/mongo/db/queryoptimizer.h
index 64a5e3a75a0..89c80241547 100644
--- a/src/mongo/db/queryoptimizer.h
+++ b/src/mongo/db/queryoptimizer.h
@@ -51,7 +51,7 @@ namespace mongo {
                                        shared_ptr<const ParsedQuery>(),
                                const BSONObj &startKey = BSONObj(),
                                const BSONObj &endKey = BSONObj(),
-                               string special="" );
+                               const std::string& special="" );
 
         /** Categorical classification of a QueryPlan's utility. */
         enum Utility {
@@ -120,7 +120,7 @@ namespace mongo {
                   const BSONObj &originalQuery,
                   const BSONObj &order,
                   const shared_ptr<const ParsedQuery> &parsedQuery,
-                  string special );
+                  const std::string& special );
         void init( const FieldRangeSetPair *originalFrsp,
                   const BSONObj &startKey,
                   const BSONObj &endKey );