alt/base_as_notnull_alt3.nit:41,6--19: Warning: expression is already not null, since it is a `A`. alt/base_as_notnull_alt3.nit:42,6--20: Warning: expression is already not null, since it is a `A`. alt/base_as_notnull_alt3.nit:43,6--19: Warning: expression is already not null, since it is a `B`. alt/base_as_notnull_alt3.nit:52,6--19: Warning: expression is already not null, since it is a `B`. alt/base_as_notnull_alt3.nit:53,6--20: Type error: expected B, got A