Swaps the contents with those ofother.

• If neither*this norother contain a value, the function has no effect.

• If only one of*this andother contains a value (let's call this objectin and the otherun), the contained value ofun isdirect-initialized fromstd::move(*in), followed by destruction of the contained value ofin as if byin.val->T::~T(). After this call,in does not contain a valueun contains a value.

• If both*this andother contain values, the contained values are exchanged by callingusingstd::swap; swap(**this,*other).T lvalues must satisfySwappable.

[edit]Parameters

[edit]Return value

(none)

[edit]Exceptions

In the case of thrown exception, the states of the contained values of*this andother are determined by the exception safety guarantees ofswap of typeT orT's move constructor, whichever is called. For both*this andother, if the object contained a value, it is left containing a value, and the other way round.

[edit]See also