Adding More Objective-C Literals to Clang
Stuart Carnie in 2012 (via Ole Begemann):
Truthfully, I’ve wanted an excuse to hack on Clang and this seemed small enough in scope to achieve in a day. I threw out the idea of NSURL literals being represented by a @@ prefix, so the following line would compile:
NSURL *url = @@"http://apple.com"