// { dg-do compile { target c++20 } }
// Test basic expression requirements
// req13.C
template<class T, class...Args>
concept Constructible =
  requires(Args&&...args) {
    T {((Args&&)(args))...};
    new T{((Args&&)(args))...};
  };
template<typename T>
  requires Constructible<T> 
struct A { };
A<int> a;
// req19.C
struct B
{
  template <class T> 
  void f(T t) requires requires (T tt) { tt; }
  { }
};
int main()
{
  B().f(42);
}