Convert multi-dimensional array to easily parsable string

Flattens array entries so that they can be parsed and/or read easily. I use this in CrossORM to make the permission definitions easy to read and write by users.

function flatten_array($array, $parents = '')
{
	if ( !is_array($array) AND !is_object($array))
	{
		return array($parents . $array);
	}

	$array  = (array) $array;
	$flat 	= array();

	foreach ($array AS $k => $v)
	{
		if (is_numeric($k))
		{
			$k = '';
			$p = $parents;
		} else
		{
			$p = $parents . $k . '.';
			$flat[] = $parents . $k;
		}

		$flat = array_merge($flat,flatten_array($v,$p));
	}

	return $flat;
}

Sample usage:

$array = flatten_array(array(
	"fruits"  	=> array(
		"a" 		=> "orange",
        "b" 		=> "banana",
        "c" 		=> "apple"
    ),
    "numbers" 	=> array (
		1, 2, 3, 4, 5, 6
	),
    "holes"   	=> array (
		"first",
        5 			=> "second",
        "third"
    )
));

echo implode('\n',$array);

Produces:

fruits
fruits.a
fruits.a.orange
fruits.b
fruits.b.banana
fruits.c
fruits.c.apple
numbers
numbers.1
numbers.2
numbers.3
numbers.4
numbers.5
numbers.6
holes
holes.first
holes.second
holes.third