+
+-- Pretty prints a tycon, using the family instance in case of a
+-- representation tycon. For example
+-- e.g. data T [a] = ...
+-- In that case we want to print `T [a]', where T is the family TyCon
+pprSourceTyCon tycon
+ | Just (repTyCon, tys) <- tyConFamInst_maybe tycon
+ = ppr $ repTyCon `TyConApp` tys -- can't be FunTyCon
+ | otherwise
+ = ppr tycon