wp_unique_id

WordPress Version: .10

/**
 * Get unique ID.
 *
 * This is a PHP implementation of Underscore's uniqueId method. A static variable
 * contains an integer that is incremented with each call. This number is returned
 * with the optional prefix. As such the returned value is not universally unique,
 * but it is unique across the life of the PHP process.
 *
 * @since 5.0.3
 *
 * @staticvar int $id_counter
 *
 * @param string $prefix Prefix for the returned ID.
 * @return string Unique ID.
 */
function wp_unique_id($prefix = '')
{
    static $id_counter = 0;
    return $prefix . (string) ++$id_counter;
}