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# std::nullopt

From cppreference.com
< cpp‎ | utility‎ | optional

Defined in header `<optional>` |  |
inline constexpr nullopt_t nullopt{/*unspecified*/}; |  | (since C++17)

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

### [edit] See also

nullopt_t (C++17) | indicator of optional type with uninitialized state (class) [edit]

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