c++ - Check function overwriting in the derived class in CRTP pattern -


i'm trying implement compile-time checking of correct implementation of crtp pattern.

here code:

#include <iostream> #include <type_traits>  using namespace std;  #define static_interface_check(baseclass, derivedclass, funcname) \     static_assert(!std::is_same<decltype(&derivedclass::funcname), decltype(&baseclass<derivedclass>::funcname)>::value, "crtp error: function " #baseclass "::" #funcname " not overwritten in class " #derivedclass);   template <class t> class interface { public:     interface();      void foo1()     {         static_cast<t*>(this)->foo1();     }      void foo2()     {         static_cast<t*>(this)->foo2();     } };  // checking inside interface<t> declaration results in incomplete type error, had move default constructor template <class t> interface<t>::interface() {     static_interface_check(interface, t, foo1);     static_interface_check(interface, t, foo2); }  class a: public interface<a> { public:     void foo1() { cout << "a::foo1()" << endl; } };  template <class t> void bar(interface<t> &obj) {     obj.foo1();     obj.foo2(); }  int main() {     a;     bar(a);      return 0; }

it fails during compilation expected:

error: static assertion failed: crtp error: function interface::foo2 not overwritten in class t

but want use function overloading, const , non-const versions of same function.

the question is: how can implement interface containing void foo(), void foo(int) , void foo(int) const?


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