69 lines
1.4 KiB
C++
69 lines
1.4 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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// constexpr optional(nullopt_t) noexcept;
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#include <experimental/optional>
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#include <type_traits>
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#include <cassert>
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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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template <class Opt>
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void
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test_constexpr()
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{
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static_assert(noexcept(Opt(nullopt)), "");
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constexpr Opt opt(nullopt);
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static_assert(static_cast<bool>(opt) == false, "");
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struct test_constexpr_ctor
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: public Opt
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{
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constexpr test_constexpr_ctor() {}
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};
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}
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template <class Opt>
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void
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test()
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{
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static_assert(noexcept(Opt(nullopt)), "");
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Opt opt(nullopt);
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assert(static_cast<bool>(opt) == false);
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struct test_constexpr_ctor
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: public Opt
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{
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constexpr test_constexpr_ctor() {}
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};
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}
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struct X
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{
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X();
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};
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#endif // _LIBCPP_STD_VER > 11
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int main()
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{
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#if _LIBCPP_STD_VER > 11
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test_constexpr<optional<int>>();
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test_constexpr<optional<int*>>();
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test<optional<X>>();
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#endif // _LIBCPP_STD_VER > 11
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}
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