-error_unk_class.nit:17,13--18: Type error: class Canard not found in module error_unk_class.
+error_unk_class.nit:16,9--12: Error: class `Fail` not found in module `error_unk_class`.
+error_unk_class.nit:17,9--15: Error: class `Boolean` not found in module `error_unk_class`. Did you mean `core::Bool`?
+error_unk_class.nit:18,9--16: Error: class `core::list::ListNode` not visible in module `error_unk_class`.
+error_unk_class.nit:19,9--13: Error: class `POSet` not found in module `error_unk_class`. Did you mean `core::Set`?