D-Programming-Language/dmd — pull request #459 by 9rnsr (2011-10-17 03:16:48+00:00)
Title: Issue 6207 - Mixin template evaluated to string can convert to string mixin expression implicitly 

http://d.puremagic.com/issues/show_bug.cgi?id=6207

If mixin template instantiation makes manifest constant string and it appears in expression context, the compiler converts it implicitly to string mixin expression.