base_isa_gen4.nit:34,8--15: Warning: expression is already a `A` since it is a `B[Canard]`.
base_isa_gen4.nit:35,8--23: Warning: expression is already a `B[Canard]`.
base_isa_gen4.nit:36,8--23: Warning: expression is already a `B[Animal]` since it is a `B[Canard]`.
base_isa_gen4.nit:40,8--26: Warning: expression is already a `B[B[Canard]]`.
base_isa_gen4.nit:42,8--26: Warning: expression is already a `B[B[Animal]]` since it is a `B[B[Canard]]`.
true