Are you having problems getting errrors about "namespace" in your apps? Can't figure out why? Everything looks OK?
The problem may be that the compiler is reporting the wrong file as having the error.
In my case, SampleApplicationSession.h was reporting the error. But of course, this is a .mm file, so I was very confused.
In fact, the file calling that code was the problem. That one had to be changed to .mm.