diff --git a/Exceptions/GenerationError.php b/Exceptions/GenerationError.php
index a11160c..ef0ce74 100644
--- a/Exceptions/GenerationError.php
+++ b/Exceptions/GenerationError.php
@@ -4,6 +4,11 @@
 
 class GenerationError extends \Exception
 {
+    /**
+     * @var mixed
+     */
+    private $newNewFile;
+
     public function __construct($newNewFile)
     {
         $this->newNewFile = $newNewFile;