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40 lines
1.1 KiB
40 lines
1.1 KiB
4 months ago
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//===----------------------------------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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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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// template <class T> constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept;
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// template <class T> constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept;
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#include <optional>
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int main()
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{
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using std::optional;
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using std::nullopt_t;
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using std::nullopt;
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{
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typedef int T;
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typedef optional<T> O;
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constexpr O o1; // disengaged
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constexpr O o2{1}; // engaged
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static_assert ( (nullopt == o1), "" );
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static_assert ( !(nullopt == o2), "" );
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static_assert ( (o1 == nullopt), "" );
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static_assert ( !(o2 == nullopt), "" );
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static_assert (noexcept(nullopt == o1), "");
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static_assert (noexcept(o1 == nullopt), "");
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}
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}
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