diff --git a/Mac/Tools/IDE/PyDebugger.py b/Mac/Tools/IDE/PyDebugger.py
index 48d6ff8..866bc1b 100644
--- a/Mac/Tools/IDE/PyDebugger.py
+++ b/Mac/Tools/IDE/PyDebugger.py
@@ -91,7 +91,7 @@
 		self.set_quit()
 		self.clear_tracefuncs()
 		self.continuewithoutdebugger = 1
-		if self.w.parent:
+		if hasattr(self, "w") and self.w.parent:
 			self.exit_mainloop()
 			self.resetwidgets()