more standard method_setup;
enforce subgoal boundaries via SUBGOAL -- clean tactical failure if out-of-range;

--- a/src/HOL/Nominal/Nominal.thy	Thu Mar 20 19:24:51 2014 +0100
+++ b/src/HOL/Nominal/Nominal.thy	Thu Mar 20 19:58:33 2014 +0100
@@ -3638,13 +3638,15 @@
 (* tactics for generating fresh names and simplifying fresh_funs *)
 ML_file "nominal_fresh_fun.ML"
 
-method_setup generate_fresh = 
-  {* setup_generate_fresh *} 
-  {* tactic to generate a name fresh for all the variables in the goal *}
-
-method_setup fresh_fun_simp = 
-  {* setup_fresh_fun_simp *} 
-  {* tactic to delete one inner occurence of fresh_fun *}
+method_setup generate_fresh = {*
+  Args.type_name {proper = true, strict = true} >>
+    (fn s => fn ctxt => SIMPLE_METHOD (generate_fresh_tac ctxt s))
+*} "generate a name fresh for all the variables in the goal"
+
+method_setup fresh_fun_simp = {*
+  Scan.lift (Args.parens (Args.$$$ "no_asm") >> K true || Scan.succeed false) >>
+    (fn b => fn ctxt => SIMPLE_METHOD' (fresh_fun_tac ctxt b))
+*} "delete one inner occurence of fresh_fun"
 
 
 (************************************************)

--- a/src/HOL/Nominal/nominal_fresh_fun.ML	Thu Mar 20 19:24:51 2014 +0100
+++ b/src/HOL/Nominal/nominal_fresh_fun.ML	Thu Mar 20 19:58:33 2014 +0100
@@ -5,7 +5,7 @@
 a tactic to analyse instances of the fresh_fun.
 *)
 
-(* FIXME proper ML structure *)
+(* FIXME proper ML structure! *)
 
 (* FIXME res_inst_tac mostly obsolete, cf. Subgoal.FOCUS *)
 
@@ -52,12 +52,11 @@
 (* A tactic to generate a name fresh for  all the free *)
 (* variables and parameters of the goal                *)
 
-fun generate_fresh_tac atom_name i thm =
+fun generate_fresh_tac ctxt atom_name = SUBGOAL (fn (goal, _) =>
  let
-   val thy = theory_of_thm thm;
+   val thy = Proof_Context.theory_of ctxt;
 (* the parsing function returns a qualified name, we get back the base name *)
    val atom_basename = Long_Name.base_name atom_name;
-   val goal = nth (prems_of thm) (i - 1);
    val ps = Logic.strip_params goal;
    val Ts = rev (map snd ps);
    fun is_of_fs_name T = Sign.of_sort thy (T, [Sign.intern_class thy ("fs_"^atom_basename)]);
@@ -76,11 +75,12 @@
 (* find the variable we want to instantiate *)
    val x = hd (Misc_Legacy.term_vars (prop_of exists_fresh'));
  in
+   fn st =>
    (cut_inst_tac_term' [(x,s)] exists_fresh' 1 THEN
    rtac fs_name_thm 1 THEN
-   etac exE 1) thm
-  handle List.Empty  => all_tac thm (* if we collected no variables then we do nothing *)
-  end;
+   etac exE 1) st
+  handle List.Empty  => all_tac st (* if we collected no variables then we do nothing *)
+ end) 1;
 
 fun get_inner_fresh_fun (Bound j) = NONE
   | get_inner_fresh_fun (v as Free _) = NONE
@@ -97,15 +97,14 @@
 (* This tactic generates a fresh name of the atom type *)
 (* given by the innermost fresh_fun                    *)
 
-fun generate_fresh_fun_tac i thm =
+fun generate_fresh_fun_tac ctxt = SUBGOAL (fn (goal, _) =>
   let
-    val goal = nth (prems_of thm) (i - 1);
     val atom_name_opt = get_inner_fresh_fun goal;
   in
   case atom_name_opt of
-    NONE => all_tac thm
-  | SOME atom_name  => generate_fresh_tac atom_name i thm
-  end
+    NONE => all_tac
+  | SOME atom_name  => generate_fresh_tac ctxt atom_name
+  end) 1;
 
 (* Two substitution tactics which looks for the innermost occurence in
    one assumption or in the conclusion *)
@@ -123,24 +122,23 @@
   curry (curry (FIRST' (map uncurry (map uncurry (map subst_inner_asm_tac_aux
             (1 upto Thm.nprems_of th)))))) ctxt th;
 
-fun fresh_fun_tac ctxt no_asm i thm =
+fun fresh_fun_tac ctxt no_asm = SUBGOAL (fn (goal, i) =>
   (* Find the variable we instantiate *)
   let
-    val thy = theory_of_thm thm;
+    val thy = Proof_Context.theory_of ctxt;
     val abs_fresh = Global_Theory.get_thms thy "abs_fresh";
     val fresh_perm_app = Global_Theory.get_thms thy "fresh_perm_app";
     val simp_ctxt =
       ctxt addsimps (fresh_prod :: abs_fresh)
       addsimps fresh_perm_app;
     val x = hd (tl (Misc_Legacy.term_vars (prop_of exI)));
-    val goal = nth (prems_of thm) (i-1);
     val atom_name_opt = get_inner_fresh_fun goal;
     val n = length (Logic.strip_params goal);
     (* Here we rely on the fact that the variable introduced by generate_fresh_tac *)
     (* is the last one in the list, the inner one *)
   in
   case atom_name_opt of
-    NONE => all_tac thm
+    NONE => all_tac
   | SOME atom_name =>
   let
     val atom_basename = Long_Name.base_name atom_name;
@@ -173,21 +171,7 @@
     (subst_inner_asm_tac ctxt fresh_fun_app' i THEN (RANGE post_rewrite_tacs i)))
     ORELSE
     (subst_inner_tac ctxt fresh_fun_app' i THEN (RANGE post_rewrite_tacs i))) st
-  end)) thm
-
+  end))
   end
-  end
+  end)
 
-(* syntax for options, given "(no_asm)" will give back true, without
-   gives back false *)
-val options_syntax =
-    (Args.parens (Args.$$$ "no_asm") >> (K true)) ||
-     (Scan.succeed false);
-
-fun setup_generate_fresh x =
-  (Args.goal_spec -- Args.type_name {proper = true, strict = true} >>
-    (fn (quant, s) => K (SIMPLE_METHOD'' quant (generate_fresh_tac s)))) x;
-
-fun setup_fresh_fun_simp x =
-  (Scan.lift options_syntax >> (fn b => fn ctxt => SIMPLE_METHOD' (fresh_fun_tac ctxt b))) x;
-

--- a/src/HOL/Nominal/nominal_permeq.ML	Thu Mar 20 19:24:51 2014 +0100
+++ b/src/HOL/Nominal/nominal_permeq.ML	Thu Mar 20 19:58:33 2014 +0100
@@ -142,7 +142,7 @@
 (* stac contains the simplifiation tactic that is *)
 (* applied (see (no_asm) options below            *)
 fun perm_simp_gen stac dyn_thms eqvt_thms ctxt i = 
-    ("general simplification of permutations", fn st =>
+    ("general simplification of permutations", fn st => SUBGOAL (fn _ =>
     let
        val ctxt' = ctxt
          addsimps (maps (dynamic_thms st) dyn_thms @ eqvt_thms)
@@ -150,8 +150,8 @@
          |> fold Simplifier.del_cong weak_congs
          |> fold Simplifier.add_cong strong_congs
     in
-      stac ctxt' i st
-    end);
+      stac ctxt' i
+    end) i st);
 
 (* general simplification of permutations and permutation that arose from eqvt-problems *)
 fun perm_simp stac ctxt =