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// 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]}}
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