std::experimental::nullopt

 

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std::experimental::optional

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optional::optional

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hash

nullopt_t

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nullopt

in_place

 

Defined in header <experimental/optional>
constexpr nullopt_t nullopt{/*unspecified*/};		(library fundamentals TS)

std::experimental::nullopt is a constant of type std::experimental::nullopt_t that is used to indicate optional type with uninitialized state.

See also

nullopt_t (library fundamentals TS)

indicator of optional type with uninitialized state (class)

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