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#include <type_traits>
#include <iostream>
 
 
template <typename T, typename M, typename ...Args>
auto invoke( T *object, M method, Args&&... args ) -> decltype( *method )
{
    return ( static_cast<T*>( object )->*method )( std::forward<Args>( args )... );
}
 
struct Foo
{
    int triple( int val )
    {
        return val * 3;
    }
};
 
int main()
{
    Foo foo;
 
    std::cout << invoke( &foo, &Foo::triple, 5 );   // output: 15
 
    return 0;
}
 

prog.cpp: In function 'int main()':
prog.cpp:23:48: error: no matching function for call to 'invoke(Foo*, int (Foo::*)(int), int)'
     std::cout << invoke( &foo, &Foo::triple, 5 );   // output: 15
                                                ^
prog.cpp:6:6: note: candidate: template<class T, class M, class ... Args> decltype (* method) invoke(T*, M, Args&& ...)
 auto invoke( T *object, M method, Args&&... args ) -> decltype( *method )
      ^
prog.cpp:6:6: note:   template argument deduction/substitution failed:
prog.cpp: In substitution of 'template<class T, class M, class ... Args> decltype (* method) invoke(T*, M, Args&& ...) [with T = Foo; M = int (Foo::*)(int); Args = {int}]':
prog.cpp:23:48:   required from here
prog.cpp:6:65: error: invalid use of unary '*' on pointer to member
 auto invoke( T *object, M method, Args&&... args ) -> decltype( *method )
                                                                 ^

Standard output is empty