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#include <iostream>
using namespace std;
 
#if 0
template <class F1, class F2>
struct overload : F1, F2 {
  overload(F1 f1, F2 f2) : F1(f1), F2(f2) { }
 
  using F1::operator();
  using F2::operator();
};
 
template <class F1, class F2>
auto make_overload(F1 f1, F2 f2) {
  return overload<F1, F2>(f1, f2);
}
#else
template <class... Fs>
struct overload;
 
template <class F0, class... Frest>
struct overload<F0, Frest...> : F0, overload<Frest...> {
  overload(F0 f0, Frest... rest) : F0(f0), overload<Frest...>(rest...) {}
 
  using F0::operator();
  using overload<Frest...>::operator();
};
 
template <class F0>
struct overload<F0> {
  overload(F0 f0) : F0(f0) {}
  using F0::operator();
};
 
template <class... Fs>
auto make_overload(Fs... fs) {
  return overload<Fs...>(fs...);
}
#endif
 
#if 0
#define CAP
#define PRINTY()
#else
#define CAP =
#define PRINTY() cout << "int y==" << y << endl
#endif
 
int main(int argc, char *argv[]) {
	int y = 123;
 
	auto f = make_overload(
		[CAP] (int x) { cout << "int x==" << x << endl; PRINTY(); },
		[CAP] (char *cp) { cout << "char *cp==" << cp << endl; PRINTY(); });
	f(argc);
	f(argv[0]);
}

prog.cpp: In instantiation of 'struct overload<main(int, char**)::<lambda(char*)> >':
prog.cpp:22:8:   required from 'struct overload<main(int, char**)::<lambda(int)>, main(int, char**)::<lambda(char*)> >'
prog.cpp:37:31:   required from 'auto make_overload(Fs ...) [with Fs = {main(int, char**)::<lambda(int)>, main(int, char**)::<lambda(char*)>}]'
prog.cpp:54:69:   required from here
prog.cpp:32:22: error: type 'main(int, char**)::<lambda(char*)>' is not a base type for type 'overload<main(int, char**)::<lambda(char*)> >'
   using F0::operator();
                      ^
prog.cpp: In instantiation of 'struct overload<main(int, char**)::<lambda(int)>, main(int, char**)::<lambda(char*)> >':
prog.cpp:37:31:   required from 'auto make_overload(Fs ...) [with Fs = {main(int, char**)::<lambda(int)>, main(int, char**)::<lambda(char*)>}]'
prog.cpp:54:69:   required from here
prog.cpp:26:38: error: no members matching 'overload<main(int, char**)::<lambda(char*)> >::operator()' in 'struct overload<main(int, char**)::<lambda(char*)> >'
   using overload<Frest...>::operator();
                                      ^
prog.cpp: In function 'int main(int, char**)':
prog.cpp:56:11: error: no match for call to '(overload<main(int, char**)::<lambda(int)>, main(int, char**)::<lambda(char*)> >) (char*&)'
  f(argv[0]);
           ^
prog.cpp:53:15: note: candidate: main(int, char**)::<lambda(int)> <near match>
   [CAP] (int x) { cout << "int x==" << x << endl; PRINTY(); },
               ^
prog.cpp:53:15: note:   conversion of argument 1 would be ill-formed:
prog.cpp:56:10: error: invalid conversion from 'char*' to 'int' [-fpermissive]
  f(argv[0]);
          ^
prog.cpp: At global scope:
prog.cpp:23:3: error: 'overload<F0, Frest ...>::overload(F0, Frest ...) [with F0 = main(int, char**)::<lambda(int)>; Frest = {main(int, char**)::<lambda(char*)>}]', declared using local type 'main(int, char**)::<lambda(int)>', is used but never defined [-fpermissive]
   overload(F0 f0, Frest... rest) : F0(f0), overload<Frest...>(rest...) {}
   ^

Standard output is empty