fork download 
  1. #include <type_traits>
  2.  
  3. template<typename U>
  4. struct Explicit
  5. {
  6. 	bool value;
  7. 	template<typename T = U, typename = std::enable_if_t<std::is_same<std::decay_t<T>, U>::value>>
  8. 	Explicit(T&& value) : value(value) { }
  9. 	operator U() { return value; }
  10. };
  11.  
  12.  
  13. void Foo(Explicit<bool> arg1 = false, int arg2 = 10, int arg3 = 20) { }
  14.  
  15. int main(int argc, char ** argv)
  16. {
  17. 	int x = 40, y = 50;
  18. 	Foo();
  19. 	Foo(true, x, y);
  20. 	Foo((bool)x, y);
  21. 	Foo(x, y);
  22. }
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
prog.cpp: In function 'int main(int, char**)':
prog.cpp:21:10: error: could not convert 'x' from 'int' to 'Explicit<bool>'
  Foo(x, y);
          ^
stdout 
Standard output is empty
https://ideone.com/3CJvqt
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!