// { dg-do compile { target c++20 } } | |
template<class From, class To> | |
concept convertible_to = requires(From (&f)(), void (&g)(To)) { g(f()); }; | |
template<class T> | |
concept Addable = | |
requires(T x){ | |
{x + x} -> convertible_to<T>; | |
}; | |
int main(){ | |
Addable auto t = 0; | |
} |