| // { dg-do compile { target c++20 } } |
| |
| // Performance test... This should be fast. |
| |
| #include <type_traits> |
| |
| template<typename T> |
| concept Destructible = std::is_destructible<T>::value; |
| template<typename T, typename... Args> |
| concept Constructible = Destructible<T> && std::is_constructible<T, Args...>::value; |
| template<typename T> |
| concept Move_constructible = Constructible<T, T&&>; |
| template<typename T> |
| concept Copy_constructible = Move_constructible<T> && Constructible<T, const T&>; |
| template<typename T, typename U> |
| concept Assignable = std::is_assignable<T, U>::value; |
| template<typename T> |
| concept Move_assignable = Assignable<T&, T&&>; |
| template<typename T> |
| concept Copy_assignable = Move_assignable<T> && Assignable<T&, const T&>; |
| template<typename T> |
| concept Copyable = Copy_constructible<T> && Copy_assignable<T>; |
| |
| template<typename T> |
| concept C1 = Copyable<T>; |
| template<typename T> |
| concept C2 = C1<T>; |
| template<typename T> |
| concept C3 = C2<T>; |
| template<typename T> |
| concept C4 = C3<T>; |
| template<typename T> |
| concept C5 = C4<T>; |
| template<typename T> |
| concept C6 = C5<T>; |
| template<typename T> |
| concept C7 = C6<T>; |
| template<typename T> |
| concept C8 = C7<T>; |
| template<typename T> |
| concept C9 = C8<T>; |
| template<typename T> |
| concept C10 = C9<T>; |
| template<typename T> |
| concept C11 = C10<T>; |
| |
| struct S1 {}; |
| struct S2 {}; |
| struct S3 {}; |
| struct S4 {}; |
| struct S5 {}; |
| struct S6 {}; |
| |
| static_assert(C11<S1>, ""); |
| static_assert(C11<S2>, ""); |
| static_assert(C11<S3>, ""); |
| static_assert(C11<S4>, ""); |
| static_assert(C11<S5>, ""); |
| static_assert(C11<S6>, ""); |
