forked from OSchip/llvm-project
68 lines
1.4 KiB
C++
68 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 const T* optional<T>::operator->() const;
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#ifdef _LIBCPP_DEBUG
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#define _LIBCPP_ASSERT(x, m) ((x) ? (void)0 : std::exit(0))
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#endif
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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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struct X
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{
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constexpr int test() const {return 3;}
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};
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struct Y
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{
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int test() const {return 2;}
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};
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struct Z
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{
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const Z* operator&() const {return this;}
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constexpr int test() const {return 1;}
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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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constexpr optional<X> opt(X{});
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static_assert(opt->test() == 3, "");
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}
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{
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constexpr optional<Y> opt(Y{});
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assert(opt->test() == 2);
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}
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{
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constexpr optional<Z> opt(Z{});
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assert(opt->test() == 1);
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}
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#ifdef _LIBCPP_DEBUG
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{
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const optional<X> opt;
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assert(opt->test() == 3);
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assert(false);
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}
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#endif // _LIBCPP_DEBUG
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#endif // _LIBCPP_STD_VER > 11
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}
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