diff --git a/lib/Slic3r/Extruder.pm b/lib/Slic3r/Extruder.pm
index 04451986c..31a25243c 100644
--- a/lib/Slic3r/Extruder.pm
+++ b/lib/Slic3r/Extruder.pm
@@ -115,6 +115,8 @@ sub retract {
         $gcode .= "G92 E0\n";
         $self->extrusion_distance(0);
     }
+    
+    return $gcode;
 }
 
 sub unretract {