PHP UUID v4 class

uuid.php

<?php

/**
 * @see http://stackoverflow.com/a/15875555
 */
class UUID
{
    public static function random()
    {
        if (function_exists('uuid_create')) {
            return uuid_create();
        } else if (function_exists('openssl_random_pseudo_bytes')) {
            $data = openssl_random_pseudo_bytes(16);
        } else if (function_exists('random_bytes')) {
            $data = random_bytes(16);
        }
        
        $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // set version to 0100
        $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // set bits 6-7 to 10

        return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
    }
}

var_dump(UUID::random());