54 lines
1.1 KiB
C++
54 lines
1.1 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 <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::bad_optional_access;
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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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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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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 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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