member (op =);
tuned;

--- a/src/Pure/Proof/reconstruct.ML	Thu Sep 21 19:05:41 2006 +0200
+++ b/src/Pure/Proof/reconstruct.ML	Thu Sep 21 19:05:56 2006 +0200
@@ -232,23 +232,26 @@
       | mk_cnstrts _ _ _ _ _ = error "reconstruct_proof: minimal proof object"
   in mk_cnstrts env [] [] Symtab.empty cprf end;
 
-fun add_term_ixns (is, t) = fold_aterms (fn Var (xi, _) => insert (op =) xi | _ => I) t is;
-
 
 (**** update list of free variables of constraints ****)
 
+val add_term_ixns = fold_aterms (fn Var (xi, _) => insert (op =) xi | _ => I);
+val add_typ_ixns = fold_atyps (fn TVar (ai, _) => insert (op =) ai | _ => I);
+
 fun upd_constrs env cs =
   let
     val Envir.Envir {asol, iTs, ...} = env;
-    val dom = Vartab.foldl (uncurry (cons o fst) o Library.swap)
-      (Vartab.foldl (uncurry (cons o fst) o Library.swap) ([], asol), iTs); 
-    val vran = Vartab.foldl (add_typ_ixns o apsnd (snd o snd))
-      (Vartab.foldl (add_term_ixns o apsnd (snd o snd)) ([], asol), iTs);
+    val dom = []
+      |> Vartab.fold (cons o #1) asol
+      |> Vartab.fold (cons o #1) iTs;
+    val vran = []
+      |> Vartab.fold (add_term_ixns o #2 o #2) asol
+      |> Vartab.fold (add_typ_ixns o #2 o #2) iTs;
     fun check_cs [] = []
       | check_cs ((u, p, vs)::ps) =
           let val vs' = subtract (op =) dom vs;
           in if vs = vs' then (u, p, vs)::check_cs ps
-             else (true, p, vs' union vran)::check_cs ps
+             else (true, p, fold (insert (op =)) vs' vran)::check_cs ps
           end
   in check_cs cs end;
 
@@ -376,7 +379,7 @@
             val tye = map (fn ((s, j), _) => (s, maxidx + 1 + j))
               (term_tvars prop) @ map (rpair ~1 o fst) tfrees ~~ Ts;
             val varify = map_type_tfree (fn p as (a, S) =>
-              if p mem tfrees then TVar ((a, ~1), S) else TFree p)
+              if member (op =) tfrees p then TVar ((a, ~1), S) else TFree p)
           in
             (maxidx', prfs', map_proof_terms (subst_TVars tye o
                map_types varify) (typ_subst_TVars tye o varify) prf)

--- a/src/Pure/Syntax/syn_ext.ML	Thu Sep 21 19:05:41 2006 +0200
+++ b/src/Pure/Syntax/syn_ext.ML	Thu Sep 21 19:05:56 2006 +0200
@@ -194,7 +194,7 @@
 
 local
 
-fun is_meta c = c mem ["(", ")", "/", "_", "\\<index>"];
+val is_meta = member (op =) ["(", ")", "/", "_", "\\<index>"];
 
 val scan_delim_char =
   $$ "'" |-- Scan.one ((not o Symbol.is_blank) andf Symbol.not_eof) ||
@@ -308,7 +308,7 @@
     val (symbs, lhs) = add_args raw_symbs typ' pris;
 
     val copy_prod =
-      lhs mem ["prop", "logic"]
+      (lhs = "prop" orelse lhs = "logic")
         andalso const <> ""
         andalso not (null symbs)
         andalso not (exists is_delim symbs);