sajty/ember — comment on commit 8d3a18082139e02ee7d250ec949b9d4961be9ee6
File: doc/template_header.h line 144
By erikhjortsberg:

Well, yes, passing by const reference is preferred, but it's up to the situation (though I agree that there's no situation when passing a string where it shouldn't be passed as const reference, unless there's some funky thread start method).