overload.hpp

#ifndef HALCHECK_LIB_FUNCTIONAL_OVERLOAD_HPP
#define HALCHECK_LIB_FUNCTIONAL_OVERLOAD_HPP
 
// IWYU pragma: private, include <halcheck/lib/functional.hpp>
 
#include <utility>
 
namespace halcheck { namespace lib {
 
template<typename... Args>
struct overload {
#ifdef HALCHECK_DOXYGEN
  explicit overload(Args... args);
#endif
};
 
template<typename T>
struct overload<T> : private T {
  using T::operator();
  explicit overload(T head) : T(std::move(head)) {}
};
 
template<typename T, typename... Args>
struct overload<T, Args...> : private T, private overload<Args...> {
  using T::operator();
  using overload<Args...>::operator();
  explicit overload(T head, Args... tail) : T(std::move(head)), overload<Args...>(std::move(tail)...) {}
};
 
template<typename... Args>
lib::overload<Args...> make_overload(Args... args) {
  return lib::overload<Args...>(std::move(args)...);
}
 
}} // namespace halcheck::lib
 
#endif