 3f433cdb8e
			
		
	
	3f433cdb8e
	
	
	
		
			
			git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@192080 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			60 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //===----------------------------------------------------------------------===//
 | |
| //
 | |
| //                     The LLVM Compiler Infrastructure
 | |
| //
 | |
| // This file is dual licensed under the MIT and the University of Illinois Open
 | |
| // Source Licenses. See LICENSE.TXT for details.
 | |
| //
 | |
| //===----------------------------------------------------------------------===//
 | |
| 
 | |
| // <optional>
 | |
| 
 | |
| // template <class T> constexpr bool operator<(const optional<T>& x, const T& v);
 | |
| // template <class T> constexpr bool operator<(const T& v, const optional<T>& x);
 | |
| 
 | |
| #include <optional>
 | |
| 
 | |
| #if _LIBCPP_STD_VER > 11
 | |
| 
 | |
| struct X
 | |
| {
 | |
|     int i_;
 | |
| 
 | |
|     constexpr X(int i) : i_(i) {}
 | |
| };
 | |
| 
 | |
| constexpr bool operator < ( const X &lhs, const X &rhs )
 | |
|     { return lhs.i_ < rhs.i_ ; }
 | |
|     
 | |
| #endif
 | |
| 
 | |
| int main()
 | |
| {
 | |
| #if _LIBCPP_STD_VER > 11
 | |
| 
 | |
|     {
 | |
|     typedef X T;
 | |
|     typedef std::optional<T> O;
 | |
|     
 | |
|     constexpr T val(2);
 | |
|     constexpr O o1;     // disengaged
 | |
|     constexpr O o2{1};  // engaged
 | |
|     constexpr O o3{val};  // engaged
 | |
| 
 | |
|     static_assert (   o1 < T(1) , "" );
 | |
|     static_assert ( !(o2 < T(1)), "" );
 | |
|     static_assert ( !(o3 < T(1)), "" );
 | |
|     static_assert (   o2 < T(2) , "" );
 | |
|     static_assert (   o2 < T(val), "" );
 | |
|     static_assert (   o3 < T(3) , "" );
 | |
| 
 | |
|     static_assert (  !(T(1) < o1), "" );
 | |
|     static_assert (  !(T(1) < o2), "" );
 | |
|     static_assert (    T(1) < o3 , "" );
 | |
|     static_assert (  !(T(2) < o2), "" );
 | |
|     static_assert (!(T(val) < o2), "" );
 | |
|     static_assert (  !(T(3) < o3), "" );
 | |
|     }
 | |
| #endif
 | |
| }
 |