de-deprecate this: https://stackoverflow.com/a/5194470/2004683

decamelize.php

function decamelize($input_string) {
    return preg_replace_callback(
        '#(^|[a-z])([A-Z])#',
        function (array $matches) {
            $result = '';
            if (0 === strlen($matches[1]))
                $result = $matches[2];
            else
                $result = "{$matches[1]}_{$matches[2]}";
            $result = strtolower($result);
            return $result;
        },
        $input_string
    );
}