-test_multiconstraint.nit:64,7: Redef error: G is an imported class. Add the redef keyword to refine it.
-test_multiconstraint.nit:70,7: Redef error: G is an imported class. Add the redef keyword to refine it.
+test_multiconstraint.nit:64,7: Error: a class `G` is already defined at line 56.
+test_multiconstraint.nit:70,7: Error: a class `G` is already defined at line 56.