Re: [Boost-users] Concept check vs enable_if

Thansk for the clues. I indeed turned to a traits based solution. I must admit that, if testing for the result_type typedef is easy, testing if a template inner class with an a priori unknown number of template parameters is harder. It's even harder cause I can't use a simple SFINAE on the result of boost::result_of cause it's defined even if neither result_of protocols are implemented. I'll try some exhaustive listing of result possibilities and see what it spawns.