+
+unTagBndr :: TaggedBndr tag -> CoreBndr
+unTagBndr (TB b _) = b
+
+unTag :: TaggedExpr tag -> CoreExpr
+unTag (Var v) = Var v
+unTag (Lit l) = Lit l
+unTag (Type ty) = Type ty
+unTag (Note n e) = Note n (unTag e)
+unTag (App e1 e2) = App (unTag e1) (unTag e2)
+unTag (Lam b e) = Lam (unTagBndr b) (unTag e)
+unTag (Cast e co) = Cast (unTag e) co
+unTag (Let (Rec prs) e) = Let (Rec [(unTagBndr b,unTag r) | (b, r) <- prs]) (unTag e)
+unTag (Let (NonRec b r) e) = Let (NonRec (unTagBndr b) (unTag r)) (unTag e)
+unTag (Case e b ty alts) = Case (unTag e) (unTagBndr b) ty
+ [(c, map unTagBndr bs, unTag r) | (c,bs,r) <- alts]