import TcSimplify ( tcSimplifyCheck, bindInstsOfLocalFuns )
import TcEnv ( newLocalName, tcExtendIdEnv1, tcExtendTyVarEnv,
tcLookupClass, tcLookupDataCon, tcLookupId )
-import TcMType ( newTyFlexiVarTy, arityErr, tcSkolTyVars, isRigidType )
+import TcMType ( newTyFlexiVarTy, arityErr, tcSkolTyVars )
import TcType ( TcType, TcTyVar, TcSigmaType, TcTauType, zipTopTvSubst,
SkolemInfo(PatSkol), isSkolemTyVar, pprSkolemTyVar,
mkTyVarTys, mkClassPred, mkTyConApp, isOverloadedTy )