std::optional::operator bool

 

C++

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rel_ops::operator!= rel_ops::operator> rel_ops::operator<= rel_ops::operator>=

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std::optional

Member functions

optional::optional

optional::~optional

optional::operator=

Observers

optional::operator-> optional::operator*

optional::operator bool

optional::value

optional::value_or

Modifiers

optional::emplace

optional::swap

Non-member functions

operator== operator<

make_optional

swap

Helper classes

hash

 

constexpr explicit operator bool() const;		(since C++14)

Checks whether *this is in engaged state, i.e. whether the contained value is initialized.

Parameters

(none)

Return value

true if *this is in engaged state, false otherwise.

Exceptions

noexcept specification:  

noexcept

  (since C++11)