NAME¶

std::experimental::optional::swap - std::experimental::optional::swap

Synopsis¶

void swap( optional& other ) noexcept(/* see below */); (library fundamentals TS)

Swaps the contents with those of other.

* If neither *this nor other contain a value, the function has no effect.
* If only one of *this and other contains a value (let's call this object in and
the other un), the contained value of un is direct-initialized from
std::move(*in), followed by destruction of the contained value of in as if by
in.val->T::~T(). After this call, in does not contain a value un contains a
value.
* If both *this and other contain values, the contained values are exchanged by
calling using std::swap; swap(**this, *other). T lvalues must satisfy Swappable.

Parameters¶

other - the optional object to exchange the contents with

Return value¶

(none)

Exceptions¶

noexcept specification:
noexcept(std::is_nothrow_move_constructible<T>::value &&
noexcept(swap(std::declval<T&>(), std::declval<T&>())))

In the case of thrown exception, the states of the contained values of *this and
other are determined by the exception safety guarantees of swap of type T or T's
move constructor, whichever is called. For both *this and other, if the object
contained a value, it is left containing a value, and the other way round.

See also¶

std::swap(std::experimental::optional) specializes the std::swap algorithm
(function)

Categories:¶

* Noindexed pages
* conditionally noexcept