/**
* Register a callback to be invoked when the current coroutine is popped
* from the call stack.
*
* The callback is guaranteed to be called even if a reference to the
* coroutine is held elsewhere (unlike a PHP finally block in a generator).
*
* @param StrandInterface $strand The currently executing strand.
* @param callable $callback The callback to invoke.
*/
public function finally_(StrandInterface $strand, callable $callback)
{
$strand->current()->registerFinalizeCallback($callback);
$strand->resumeWithValue(null);
}
