splitSigmaTy, splitAppTy, isTyVarTy, matchTy, mkSigmaTy,
getTyCon_maybe, maybeBoxedPrimType, splitRhoTy, eqTy
)
-import TyVar ( GenTyVar, GenTyVarSet(..), mkTyVarSet, unionTyVarSets )
+import TyVar ( GenTyVar, SYN_IE(GenTyVarSet), mkTyVarSet, unionTyVarSets )
import TysWiredIn ( stringTy )
import Unique ( Unique )
import Util ( zipEqual, panic )