private function isHeaderIndexLine(string $line): bool
    {
        $matches = [];
        if (preg_match('#^index\s([a-z0-9]+)\.\.([a-z0-9]+)(.*)$#i', $line, $matches)) {
            $this->currentFile = new File($this->currentFileName, $this->currentOperation);
            return true;
        }
        return false;
    }