| // RUN: %clang_cc1 -std=c++2a -x c++ %s -verify |
| |
| using A = int; |
| |
| template<typename T, typename U> |
| constexpr bool is_same_v = false; |
| |
| template<typename T> |
| constexpr bool is_same_v<T, T> = true; |
| |
| template<typename T, typename U> |
| concept same_as = is_same_v<T, U>; |
| |
| static_assert(requires { requires true; 0; typename A; |
| { 0 } -> same_as<int>; }); |
| static_assert(is_same_v<bool, decltype(requires { requires false; })>); |
| |
| // Check that requires expr is an unevaluated context. |
| struct Y { |
| int i; |
| static constexpr bool r = requires { i; }; |
| }; |
| |
| template<typename T> requires requires (T t) { |
| requires false; // expected-note{{because 'false' evaluated to false}} |
| requires false; |
| requires requires { |
| requires false; |
| }; |
| } |
| struct r1 { }; |
| |
| using r1i = r1<int>; |
| // expected-error@-1 {{constraints not satisfied for class template 'r1' [with T = int]}} |
| |
| template<typename T> requires requires (T t) { |
| requires requires { |
| requires false; // expected-note{{because 'false' evaluated to false}} |
| }; |
| } |
| struct r2 { }; |
| |
| using r2i = r2<int>; |
| // expected-error@-1 {{constraints not satisfied for class template 'r2' [with T = int]}} |
| |
| template<typename T> requires requires (T t) { |
| requires requires { |
| requires true; |
| }; |
| requires true; |
| requires requires { |
| requires false; // expected-note{{because 'false' evaluated to false}} |
| }; |
| } |
| struct r3 { }; |
| |
| using r3i = r3<int>; |
| // expected-error@-1 {{constraints not satisfied for class template 'r3' [with T = int]}} |
| |
| template<typename T> |
| struct S { static const int s = T::value; }; |
| |
| template<typename T> requires requires { T::value; S<T>::s; } |
| // expected-note@-1 {{because 'T::value' would be invalid: type 'int' cannot be used prior to '::' because it has no members}} |
| struct r4 { }; |
| |
| using r4i = r4<int>; |
| // expected-error@-1 {{constraints not satisfied for class template 'r4' [with T = int]}} |