Add multiple dispatch tool #14

#include <type_traits>
#include <functional>

template <typename Ret, typename... Arg, typename... Param>
constexpr auto strict_invoke(Ret (*f)(Arg...),
                             Param&&... param) noexcept(false) -> Ret
  requires(
      std::is_same_v<std::remove_cvref_t<Arg>, std::remove_cvref_t<Param>> &&
      ...)
      && std::is_invocable_v<decltype(f), decltype(param)...>

{
  return f(std::forward<Param>(param)...);
}

double add(double lhs, double rhs) {
  return lhs + rhs;
}

int main()
{
  add(2.3f, 1.3f); // works
  add(2, 1); // works
  //strict_invoke(&add, 2.3f, 1.3f); // fails, requires conversion
  strict_invoke(&add, 1.3, 1.3); // works
  //strict_invoke(&add, 1, 2); // fails, requires conversion
}