defer (1 of 3 overloads)

Submits a completion token or function object for execution.

template<
    typename CompletionToken>
DEDUCED defer(
    CompletionToken && token);

This function submits an object for execution using the object's associated executor. The function object is queued for execution, and is never called from the current thread prior to returning from defer().

This function has the following effects:

Constructs a function object handler of type Handler, initialized with handler(forward<CompletionToken>(token)).
Constructs an object result of type async_result<Handler>, initializing the object as result(handler).
Obtains the handler's associated executor object ex by performing get_associated_executor(handler).
Obtains the handler's associated allocator object alloc by performing get_associated_allocator(handler).
Performs ex.defer(std::move(handler), alloc).
Returns result.get().