std::nullopt
Defined in header <optional> | ||
|---|---|---|
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.
See also
|
(C++17) | indicator of an std::optional that does not contain a value (class) |
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