php str 4-6 40-46 comma explode str array array foreach comma as value

<?php

$str = '1,4-6,7,40-46/2';
$comma = explode(',', $str);

$array = array();

foreach ($comma as $value) {
    if (preg_match('#^([0-9]+)\-([0-9]+)/([0-9]+)$#', $value, $match)) {
        $start = (int) $match[1];
        $limit = (int) $match[2];
        $step = (int) $match[3];
        for ($i = $start; $i <= $limit; $i += $step) {
            $array[] = $i;
        }
    } else if (preg_match('#^([0-9]+)\-([0-9]+)$#', $value, $match)) {
        $start = (int) $match[1];
        $limit = (int) $match[2];
        for ($i = $start; $i <= $limit; ++$i) {
            $array[] = $i;
        }
    } else if (preg_match('#^([0-9]+)$#', $value, $match)) {
        $array[] = (int) $match[0];
    }
}

var_dump($array);