src/Routes/UrlManager.php
public function extractStaticPart($path) {
        $pos = $this->findPlaceholderStartPos($path);
        if ($pos !== false) {
            $prefix = substr($path, 0, $pos);
            return strlen($prefix) > 1 ? rtrim($prefix, '/') : $prefix;
        }
        return $path;
    }
public function extractStaticPart($path) {
        $pos = $this->findPlaceholderStartPos($path);
        if ($pos !== false) {
            $prefix = substr($path, 0, $pos);
            return strlen($prefix) > 1 ? rtrim($prefix, '/') : $prefix;
        }
        return $path;
    }
Extract static part from url (without placeholders)
@param string $path
@return string