public function debug() {
        echo "filePath    = " . $this->filePath . PHP_EOL;
        echo "startMarker = " . $this->startMarker . PHP_EOL;
        echo "endMarker   = " . $this->endMarker . PHP_EOL;
        echo "startIndex  = " . $this->startIndex . PHP_EOL;
        echo "endIndex    = " . $this->endIndex . PHP_EOL;
        echo "numLines    = " . $this->numLines . PHP_EOL;
        echo "Start       = " . print_r($this->beforeLines, true);
        echo "Auto      = " . print_r($this->autoLines, true);
        echo "End         = " . print_r($this->afterLines, true);
        return $this;
    }