What do you want to achieve? The shown code of course could just call m.Go(45.3); or could store a pointer to member function.   Does p have the right type? Even for the 95% of implementations, it would need two parameters or alternatively it would need a different type than a 'normal' non-member function.     -----Ursprüngliche Nachricht----- Von:Frederick Virchanza Gotham via Std-Proposals <std-proposals_at_[hidden]> Gesendet:Fr 05.01.2024 13:40 Betreff:[std-proposals] Allow conversion of memfunc pointers to func pointers An:std-proposals <std-proposals_at_[hidden]>; CC:Frederick Virchanza Gotham <cauldwell.thomas_at_[hidden]>; At least 95% of C++ implementations nowadays use a calling convention that performs the invocation of a class's member function by moving all the arguments down one position, and putting the 'this' pointer in the first position. So for example on x86_64 on Microsoft Windows, if a normal function takes three integer arguments, these arguments will be put in RCX, RDX, R8. If a member function takes three integer arguments, then RCX,RDX,R8 will be moved down to RDX,R8,R9 and then the 'this' pointer will be put in RCX. Only about 4 implementations of C++ leave the function arguments alone and store the 'this' pointer in another register (for a list of them, see page 4 of http://www.virjacode.com/papers/paper_nrvo_latest.pdf ). So anyway, what if we were able to do the following in Standard C++?    struct Monkey {        unsigned i;        virtual unsigned Go(double x) { return i + static_cast<unsigned>(x + 0.5); }    };    int main(void)    {        Monkey m = { 8u };        unsigned (*p)(double) = std::memfunc_to_func( &Monkey::Go, &m );        std::invoke_func_as_memfunc(p, &m, 45.3);    } The function 'memfunc_to_func' would take two arguments:    (1) A pointer to a member function for class T    (2) A pointer to an object of type T It needs the second argument just in case the member function is virtual and it needs to look at the vtable of the supplied object. The function 'invoke_fun_as_memfunc' takes two or more arguments:    (1) A normal function pointer which holds the address of a member function    (2) An address of an object    (3) Any arguments to  be passed to the member function -- Std-Proposals mailing list Std-Proposals_at_[hidden] https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals