+----------------
+hsSigsFVs sigs = plusFVs (map hsSigFVs sigs)
+
+hsSigFVs (Sig v ty _) = extractHsTyNames ty
+hsSigFVs (SpecInstSig ty _) = extractHsTyNames ty
+hsSigFVs (SpecSig v ty _) = extractHsTyNames ty
+hsSigFVs (ClassOpSig _ _ ty _) = extractHsTyNames ty
+hsSigFVs other = emptyFVs
+
+----------------
+instDeclFVs (InstDecl inst_ty _ _ maybe_dfun _)
+ = extractHsTyNames inst_ty `plusFV`
+ (case maybe_dfun of { Just n -> unitFV n; Nothing -> emptyFVs })
+
+----------------
+ruleDeclFVs (HsRule _ _ _ _ _ _) = emptyFVs
+ruleDeclFVs (IfaceRule _ vars _ args rhs _)
+ = delFVs (map ufBinderName vars) $
+ ufExprFVs rhs `plusFV` plusFVs (map ufExprFVs args)
+
+----------------
+conDeclFVs (ConDecl _ _ tyvars context details _)
+ = delFVs (map hsTyVarName tyvars) $
+ extractHsCtxtTyNames context `plusFV`
+ conDetailsFVs details
+
+conDetailsFVs (VanillaCon btys) = plusFVs (map bangTyFVs btys)
+conDetailsFVs (InfixCon bty1 bty2) = bangTyFVs bty1 `plusFV` bangTyFVs bty2
+conDetailsFVs (RecCon flds) = plusFVs [bangTyFVs bty | (_, bty) <- flds]
+
+bangTyFVs bty = extractHsTyNames (getBangType bty)
+
+----------------
+hsIdInfoFVs (HsUnfold _ unf) = ufExprFVs unf
+hsIdInfoFVs (HsWorker n) = unitFV n
+hsIdInfoFVs other = emptyFVs
+
+----------------
+ufExprFVs (UfVar n) = unitFV n
+ufExprFVs (UfLit l) = emptyFVs
+ufExprFVs (UfLitLit l ty) = extractHsTyNames ty
+ufExprFVs (UfCCall cc ty) = extractHsTyNames ty
+ufExprFVs (UfType ty) = extractHsTyNames ty
+ufExprFVs (UfTuple tc es) = hsTupConFVs tc `plusFV` plusFVs (map ufExprFVs es)
+ufExprFVs (UfLam v e) = ufBndrFVs v (ufExprFVs e)
+ufExprFVs (UfApp e1 e2) = ufExprFVs e1 `plusFV` ufExprFVs e2
+ufExprFVs (UfCase e n as) = ufExprFVs e `plusFV` delFV n (plusFVs (map ufAltFVs as))
+ufExprFVs (UfNote n e) = ufNoteFVs n `plusFV` ufExprFVs e
+ufExprFVs (UfLet (UfNonRec b r) e) = ufExprFVs r `plusFV` ufBndrFVs b (ufExprFVs e)
+ufExprFVs (UfLet (UfRec prs) e) = foldr ufBndrFVs
+ (foldr (plusFV . ufExprFVs . snd) (ufExprFVs e) prs)
+ (map fst prs)
+
+ufBndrFVs (UfValBinder n ty) fvs = extractHsTyNames ty `plusFV` delFV n fvs
+ufBndrFVs (UfTyBinder n k) fvs = delFV n fvs
+
+ufAltFVs (con, vs, e) = ufConFVs con `plusFV` delFVs vs (ufExprFVs e)
+
+ufConFVs (UfDataAlt n) = unitFV n
+ufConFVs (UfTupleAlt t) = hsTupConFVs t
+ufConFVs (UfLitLitAlt _ ty) = extractHsTyNames ty
+ufConFVs other = emptyFVs
+
+ufNoteFVs (UfCoerce ty) = extractHsTyNames ty
+ufNoteFVs note = emptyFVs
+
+hsTupConFVs (HsTupCon n _ _) = unitFV n