c++ - Why member functions can't be used as template arguments? -


why member functions cannot used template arguments? example, want like: 

struct foo {     void bar() { //     } }; template <typename towner, void(&func)()> void call(towner *p) {     p->func(); } int main() {     foo a;     call<foo, foo::bar>(&a);     return 0; }

i know similar thing can done using pointers-to-member; well, it's cool enough of time, i'm curious why pointers "should" used.

i see no ambiguity of interpreting "p->func()" above. why standard prohibits use member functions template arguments? static member functions not allowed according compiler (vc++ 2013). know reason? or, there way same thing without loss of performance due pointer dereferencing?

thank you.

they can used non-type parameters, need use right syntax

struct foo {     void bar() { //     } }; template <typename towner, void(towner::*func)()> void call(towner *p) {     (p->*func)(); } int main() {     foo a;     call<foo, &foo::bar>(&a);     return 0; }

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