44 lines
1.0 KiB
C++
44 lines
1.0 KiB
C++
//===----------------------------------------------------------------------===//
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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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// struct nullopt_t{see below};
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// constexpr nullopt_t nullopt(unspecified);
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#include <experimental/optional>
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#include <type_traits>
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#if _LIBCPP_STD_VER > 11
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using std::experimental::optional;
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using std::experimental::nullopt_t;
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using std::experimental::nullopt;
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constexpr
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int
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test(const nullopt_t&)
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{
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return 3;
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}
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#endif
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int main()
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{
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#if _LIBCPP_STD_VER > 11
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static_assert((std::is_class<nullopt_t>::value), "");
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static_assert((std::is_empty<nullopt_t>::value), "");
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static_assert((std::is_literal_type<nullopt_t>::value), "");
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static_assert((!std::is_default_constructible<nullopt_t>::value), "");
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static_assert(test(nullopt) == 3, "");
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#endif
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}
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