forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			40 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			40 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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| 
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| // UNSUPPORTED: c++98, c++03, c++11
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| // <optional>
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| 
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| // template <class T> constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept;
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| // template <class T> constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept;
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| 
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| #include <experimental/optional>
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| 
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| int main()
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| {
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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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| 
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|     {
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|     typedef int T;
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|     typedef optional<T> O;
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| 
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|     constexpr O o1;     // disengaged
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|     constexpr O o2{1};  // engaged
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| 
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|     static_assert (  (nullopt == o1), "" );
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|     static_assert ( !(nullopt == o2), "" );
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|     static_assert (  (o1 == nullopt), "" );
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|     static_assert ( !(o2 == nullopt), "" );
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| 
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|     static_assert (noexcept(nullopt == o1), "");
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|     static_assert (noexcept(o1 == nullopt), "");
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|     }
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| }
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