std::nullopt - cppreference.com (original) (raw)

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std::optional

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optional::operator->optional::operator*
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operator==operator!=operator<operator<=operator>operator>=operator<=>(C++20)
make_optional
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hash std::optional
nullopt_t
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bad_optional_access
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nullopt
in_place

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

std::nullopt is a constant of type std::nullopt_t. Used to indicate that an std::optional does not contain a value.

[edit] See also

nullopt_t(C++17)	indicator of an std::optional that does not contain a value (class) [edit]

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