PHP library to use iterators and arrays with method chain.
$pipe = IteratorPipe::factory(array(11, 12, 13, 14))
->filter(function($k, $v) {return $v % 2 === 0; })
->map(function($k, $v) {return $v / 2; });
$pipe->toArray(); // array(1 => 6, 3 => 7)