1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20, c++23 10 11 // <functional> 12 13 // template<auto f> constexpr unspecified not_fn() noexcept; 14 // Mandates: If is_pointer_v<F> || is_member_pointer_v<F> is true, then f != nullptr is true. 15 16 #include <functional> 17 18 struct X {}; 19 20 void test() { 21 auto not_fn1 = std::not_fn<static_cast<bool (*)()>(nullptr)>(); 22 // expected-error@*:* {{static assertion failed due to requirement 'nullptr != nullptr': f cannot be equal to nullptr}} 23 24 auto not_fn2 = std::not_fn<static_cast<bool X::*>(nullptr)>(); 25 // expected-error@*:* {{static assertion failed due to requirement 'nullptr != nullptr': f cannot be equal to nullptr}} 26 27 auto not_fn3 = std::not_fn<static_cast<bool (X::*)()>(nullptr)>(); 28 // expected-error@*:* {{static assertion failed due to requirement 'nullptr != nullptr': f cannot be equal to nullptr}} 29 } 30