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44 lines
1.1 KiB
C++
44 lines
1.1 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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// UNSUPPORTED: c++98, c++03, c++11, c++14
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// <optional>
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// struct nullopt_t{see below};
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// inline constexpr nullopt_t nullopt(unspecified);
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// [optional.nullopt]/2:
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// Type nullopt_t shall not have a default constructor or an initializer-list
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// constructor, and shall not be an aggregate.
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#include <optional>
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#include <type_traits>
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#include "test_macros.h"
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using std::nullopt_t;
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using std::nullopt;
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constexpr bool test()
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{
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nullopt_t foo{nullopt};
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(void)foo;
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return true;
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}
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int main(int, char**)
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{
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static_assert(std::is_empty_v<nullopt_t>);
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static_assert(!std::is_default_constructible_v<nullopt_t>);
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static_assert(std::is_same_v<const nullopt_t, decltype(nullopt)>);
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static_assert(test());
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return 0;
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}
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