/**
* Invoke a value if it is callable.
*
* @param array $args optional array of arguments to pass to the optional callable
* @return Chain the result of the invocation wrapped into a Chain, or empty Chain
*/
public function invokeArray(array $args = []) : Chain
{
return $this->continue(conditionally(is_callable, curry(reverse(call_user_func_array), 2)($args)));
}
/**
* Find last element of the stream (optionally matched with predicate).
*
* This is a closing operation (it calls <code>$this->close()</code> internally).
*
* @param callable $predicate the predicate (optional)
* @return Optional an optional result
* @see \monad\Stream::close()
*/
public function findLast(callable $predicate = null) : Optional
{
return $this->bindMonad(sequence(curry(reverse(array_reverse))(true), curry(function ($predicate, array $array) {
return $this->find($predicate, $array);
}, 2)($predicate), optional));
}