Wait for the operation to complete, consuming the eager operation.

template<
    typename CompletionToken>
auto operator()(
    CompletionToken && token);

The wait consumes the eager operation, so this call operator must be invoked on an rvalue. Ownership passes to the completion token. When the token is a lazy one, such as deferred, destroying the resulting operation without initiating the wait detaches from the eager operation.

Remarks

The operation may be waited on at most once. Invoking a consumed or moved-from eager operation results in undefined behaviour.