base_isa_nullable1.nit:39,8--15: Warning: expression is already a `A` since it is a `B[Integer]`.
base_isa_nullable1.nit:40,8--24: Warning: expression is already a `B[Integer]`.
base_isa_nullable1.nit:41,8--25: Warning: expression is already a `B[Discrete]` since it is a `B[Integer]`.
base_isa_nullable1.nit:46,8--27: Warning: expression is already a `B[B[Integer]]`.
base_isa_nullable1.nit:48,8--28: Warning: expression is already a `B[B[Discrete]]` since it is a `B[B[Integer]]`.
base_isa_nullable1.nit:50,8--34: Warning: expression is already a `B[nullable Discrete]` since it is a `B[Integer]`.
true