Filter recursive

filter_recursive.php

<?php

function filter_recursive($data, $predicate = null)
{
	if ($predicate == null) {
		$predicate = function ($value) { return !empty($value); };
	}

	$is_object = false;
	if (is_object($data)) {
		$is_object = true;
		$data = (array) $data;
	}

	$filtered_data = array();

	foreach($data as $key => $value) {
		if (is_array($value) || is_object($value)) {
			$result = filter_recursive($value, $predicate);
			if (!empty($result)) {
				$filtered_data[$key] = filter_recursive($value, $predicate);
			}
		} elseif ($predicate($value)) {
			$filtered_data[$key] = $value;
		}
	}

	if ($is_object) {
		return (object) $filtered_data;
	} else {
		return $filtered_data;
	}
}