tyvars
[] -- No stupid theta
(DataTyCon cons is_enum)
- [] -- No record selectors
NoParentTyCon
is_rec
True -- All the wired-in tycons have generics
[] -- No existential type variables
[] -- No equality spec
[] -- No theta
- arg_tys tycon
+ arg_tys (mkTyConApp tycon (mkTyVarTys tyvars))
+ tycon
[] -- No stupid theta
(mkDataConIds bogus_wrap_name wrk_name data_con)