alt/error_virtual_type2_alt4.nit:29,10--13: Error: class `FAIL` not found in module `error_virtual_type2_alt4`.
alt/error_virtual_type2_alt4.nit:38,23: Redef Error: expected `Comparable` for return type; got `T`.
alt/error_virtual_type2_alt4.nit:40,17--27: Redef Error: expected `null` bound type; got `G[Discrete]`.
alt/error_virtual_type2_alt4.nit:42,23: Redef Error: expected `Comparable` for return type; got `T`.