llvm-project/libcxx/test/std/concepts/concepts.callable/concept.predicate/predicate.subsumption.compile.pass.cpp
Joe Loser d2baefae68
[libc++] Replace _LIBCPP_HAS_NO_CONCEPTS with _LIBCPP_STD_VER > 17. NFCI.
All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.

Differential Revision: https://reviews.llvm.org/D121528
2022-03-13 12:32:06 -04:00

31 lines
822 B
C++

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// template<class F, class... Args>
// concept predicate;
#include <concepts>
constexpr bool check_subsumption(std::regular_invocable auto) {
return false;
}
// clang-format off
template<class F>
requires std::predicate<F> && true
constexpr bool check_subsumption(F)
{
return true;
}
// clang-format on
static_assert(!check_subsumption([] {}));
static_assert(check_subsumption([] { return true; }));