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C++

Reference

<future>

promise

function template
<future>

std::swap (promise)

template <class T>  void swap (promise<T>& x, promise<T>& y) noexcept;
Swap promises
Exchanges the shared states (or lack of) between x and y.

This is an overload of swap that behaves as if x.swap(y) was called.

Parameters

x,y
promise objects of the same type (with the same template parameter).

Return value

none

Data races

Both objects, x and y, are modified.

Exception safety

No-throw guarantee: never throws exceptions.

See also

promise::swap
Swap shared states (public member function)
promise::operator=
Move-assign promise (public member function)
swap
Exchange values of two objects (function template)