| libsigc++
    2.4.1
    | 
Deduce the return type of a functor. More...
#include <sigc++/adaptors/deduce_result_type.h>
| Public Types | |
| typedef functor_trait< T_functor >::result_type | type | 
Deduce the return type of a functor.
typename deduce_result_type<functor_type, list of arg_types>::type deduces a functor's result type if functor_type inherits from sigc::functor_base and defines result_type or if functor_type is actually a (member) function type. Multi-type functors are not supported.
sigc++ adaptors use typename deduce_result_type<functor_type, list of arg_types>::type to determine the return type of their templated operator() overloads.
Adaptors in turn define a nested template class deduce_result_type that is used by template specializations of the global deduce_result_type template to correctly deduce the return types of the adaptor's suitable template operator() overload. 
| typedef functor_trait<T_functor>::result_type sigc::deduce_result_type< T_functor, T_arg1, T_arg2, T_arg3, T_arg4, T_arg5, T_arg6, T_arg7, I_derives_adaptor_base >::type | 
 1.8.9.1
 1.8.9.1