base_isa_nullable1.nit:39,8--15: Warning: expression is already a `A` since it is a `B[Integer]`. base_isa_nullable1.nit:41,8--24: Warning: expression is already a `B[Discrete]` since it is a `B[Integer]`. base_isa_nullable1.nit:46,8--25: Warning: expression is already a `B[B[Integer]]`. base_isa_nullable1.nit:48,8--26: Warning: expression is already a `B[B[Discrete]]` since it is a `B[B[Integer]]`. base_isa_nullable1.nit:50,8--33: Warning: expression is already a `B[nullable Discrete]` since it is a `B[Discrete]`. true