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    libstdc++
    
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Macros | |
| #define | __cpp_lib_experimental_optional | 
Variables | |
| constexpr in_place_t | std::experimental::in_place | 
| constexpr nullopt_t | std::experimental::nullopt | 
Class template for optional values and surrounding facilities, as described in n3793 "A proposal to add a utility class to represent optional objects (Revision 5)".
| #define __cpp_lib_experimental_optional | 
Definition at line 64 of file experimental/optional.
      
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  constexpr | 
Tag for in-place construction.
Definition at line 77 of file experimental/optional.
      
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  constexpr | 
Tag to disengage optional objects.
Definition at line 96 of file experimental/optional.