protected function getRegex($operators)
    {
        $regexes = [];

        /** @var \Xylemical\Expressions\Operator $operator */
        foreach ($operators as $operator)
        {
            $regexes[] = $operator->getRegex();
        }

        // Add parentheses regexes.
        $regexes[] = '\(';
        $regexes[] = '\)';
        $regexes[] = ',';

        // Generate the full regex.
        return '#(?:' . implode('|', $regexes) . ')#i';
    }