diff --git a/creole/var_loader.py b/creole/var_loader.py
index a50f709..ba87564 100644
--- a/creole/var_loader.py
+++ b/creole/var_loader.py
@@ -835,6 +835,11 @@ class CreoleConstraint():
                     target in self.auto.keys()) and not vdata['redefine']):
                 raise Exception(_(u"Computing function already defined for {0}").format(
                                 target))
+            if _type != 'check':
+                if target in self.fill:
+                    del(self.fill[target])
+                if target in self.auto:
+                    del(self.auto[target])
             data[target] = (func_name, params)
         return data