std::optional<T>::operator bool, std::optional<T>::has_value

< cpp‎ | utility‎ | optional
 
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std::optional
 
constexpr explicit operator bool() const noexcept;
 (since C++17)
constexpr bool has_value() const noexcept;
 (since C++17)

Checks whether *this contains a value.

Parameters

(none)

Return value

true if *this contains a value, false if *this does not contain a value.