38 lines
1.0 KiB
C++
38 lines
1.0 KiB
C++
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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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// <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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#if _LIBCPP_STD_VER > 11
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{
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typedef int T;
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typedef std::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 ( std::nullopt == o1 , "" );
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static_assert ( !(std::nullopt == o2), "" );
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static_assert ( o1 == std::nullopt , "" );
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static_assert ( !(o2 == std::nullopt), "" );
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static_assert (noexcept(std::nullopt == o1), "");
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static_assert (noexcept(o1 == std::nullopt), "");
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}
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#endif
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}
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