Flatten a multidimensional array to a single dimensional array by joining nested keys together

array_linearize.php

<?php
/**
 * Flatten a multidimensional array to a single dimensional array by joining nested keys together
 *
 * @param  array  $array The array to flatten
 * @param  string $glue  Glue string to join keys together
 * @return array
 */
function array_linearize(array $array, $glue = '/')
{
    $output = array();
    foreach ($array as $k => $v) {
        if (is_array($v)) {
            foreach (array_linearize($v, $glue) as $k2 => $v2) {
                $output[$k.$glue.$k2] = $v2;
            }
        } else {
            $output[$k] = $v;
        }
    }
    return $output;
}

/**
 * Example :
 *
 * Array
 * (
 *     [0] => 0
 *     [foo] => bar
 *     [nested] => Array
 *     (
 *         [0] => 0
 *         [foo] => bar
 *         [nested] => Array()
 *     )
 * )
 *
 * will give :
 *
 * Array
 * (
 *     [0] => 0
 *     [foo] => bar
 *     [nested/0] => 0
 *     [nested/foo] => bar
 * )
 */