Keevitaja\Linguist\Http\Kernel::defineLocale PHP Method

    public function defineLocale()
    {
        $config = ['default' => __DIR__ . '/../../config/linguist.php', 'published' => base_path('config/linguist.php')];
        if (file_exists($config['published'])) {
            $config = (include $config['published']);
        } else {
            $config = (include $config['default']);
        }
        $pattern = '/^\\/(' . implode('|', $config['locales']) . ')(?:\\/|$)/';
        $uri = filter_input(INPUT_SERVER, 'REQUEST_URI', FILTER_SANITIZE_URL);
        if (preg_match($pattern, $uri, $matches)) {
            $_SERVER['REQUEST_URI'] = preg_replace($pattern, '/', $uri);
            define('LOCALE', $matches[1]);
        }
    }