01afa5c6e4
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@189772 91177308-0d34-0410-b5e6-96231b3b80d8
51 lines
1.0 KiB
C++
51 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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// T& optional<T>::value();
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#include <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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struct X
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{
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X() = default;
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X(const X&) = delete;
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constexpr int test() const {return 3;}
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int test() {return 4;}
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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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{
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std::optional<X> opt;
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opt.emplace();
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assert(opt.value().test() == 4);
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}
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{
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std::optional<X> opt;
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try
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{
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opt.value();
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assert(false);
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}
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catch (const std::bad_optional_access&)
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{
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}
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}
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#endif // _LIBCPP_STD_VER > 11
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}
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