17 Mar
2011
17 Mar
'11
5:51 p.m.
I'm not much concerned whether it's possible to check for void return types as I can't think of a use for that ;-)
Joining the discussion a bit late... isn't it possible with typeof/decltype? In which case the library should allow it, even if it's not possible on all compilers.
Good catch - use decltype to get the return type and pass to is_convertible. Of course it complicates the implementation.... John.