X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_tactics%2FnTactics.ml;h=f5ae3a721e4880a955d4be5463252cf4423e2a36;hb=12f96bd48b460d06f9858a334ee7c52d6831712f;hp=b64ef34f2087457e50dd6330f85436ec70dbcb6b;hpb=b438322c4140e3d2395d693e9c5f0e96934436a0;p=helm.git

diff --git a/helm/software/components/ng_tactics/nTactics.ml b/helm/software/components/ng_tactics/nTactics.ml
index b64ef34f2..f5ae3a721 100644
--- a/helm/software/components/ng_tactics/nTactics.ml
+++ b/helm/software/components/ng_tactics/nTactics.ml
@@ -13,7 +13,7 @@
 
 open Printf
 
-let debug = true
+let debug = false
 let debug_print s = if debug then prerr_endline (Lazy.force s) else ()
 
 open Continuationals.Stack
@@ -21,11 +21,15 @@ open NTacStatus
 module Ast = CicNotationPt
 
 let id_tac status = status ;;
-let print_tac message status = prerr_endline message; status ;;
+let print_tac print_status message status = 
+  if print_status then pp_status status;
+  prerr_endline message; 
+  status
+;;
 
 let dot_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | ([], _, [], _) :: _ as stack ->
         (* backward compatibility: do-nothing-dot *)
@@ -39,25 +43,26 @@ let dot_tac status =
             (([ loc ], t, k, tag) :: s)
         | _ -> fail (lazy "can't use \".\" here")
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
-let branch_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+let branch_tac ?(force=false) status =
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | (g, t, k, tag) :: s ->
           match init_pos g with (* TODO *)
-          | [] | [ _ ] -> fail (lazy "too few goals to branch");
+          | [] -> fail (lazy "empty goals")
+	  | [_] when (not force) -> fail (lazy "too few goals to branch")
           | loc :: loc_tl ->
                ([ loc ], [], [], `BranchTag) :: (loc_tl, t, k, tag) :: s
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let shift_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | (g, t, k, `BranchTag) :: (g', t', k', tag) :: s ->
           (match g' with
           | [] -> fail (lazy "no more goals to shift")
@@ -66,12 +71,12 @@ let shift_tac status =
                 :: (loc_tl, t', k', tag) :: s))
      | _ -> fail (lazy "can't shift goals here")
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let pos_tac i_s status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | ([ loc ], t, [],`BranchTag) :: (g', t', k', tag) :: s
       when is_fresh loc ->
@@ -80,35 +85,55 @@ let pos_tac i_s status =
            :: (([ loc ] @+ g') @- l_js, t', k', tag) :: s)
     | _ -> fail (lazy "can't use relative positioning here")
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
+;;
+
+let case_tac lab status =
+  let gstatus = 
+    match status#stack with
+    | [] -> assert false
+    | ([ loc ], t, [],`BranchTag) :: (g', t', k', tag) :: s
+      when is_fresh loc ->
+        let l_js =
+          List.filter 
+           (fun curloc -> 
+              let _,_,metasenv,_,_ = status#obj in
+              match NCicUtils.lookup_meta (goal_of_loc curloc) metasenv with
+                  attrs,_,_ when List.mem (`Name lab) attrs -> true
+                | _ -> false) ([loc] @+ g') in
+          ((l_js, t , [],`BranchTag)
+           :: (([ loc ] @+ g') @- l_js, t', k', tag) :: s)
+    | _ -> fail (lazy "can't use relative positioning here")
+  in
+   status#set_stack gstatus
 ;;
 
 let wildcard_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | ([ loc ] , t, [], `BranchTag) :: (g', t', k', tag) :: s
        when is_fresh loc ->
             (([loc] @+ g', t, [], `BranchTag) :: ([], t', k', tag) :: s)
     | _ -> fail (lazy "can't use wildcard here")
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let merge_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | (g, t, k,`BranchTag) :: (g', t', k', tag) :: s ->
         ((t @+ filter_open g @+ g' @+ k, t', k', tag) :: s)
     | _ -> fail (lazy "can't merge goals here")
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
       
 let focus_tac gs status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | s -> assert(gs <> []);
           let stack_locs =
@@ -122,22 +147,23 @@ let focus_tac gs status =
             gs;
           (zero_pos gs, [], [], `FocusTag) :: deep_close gs s
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let unfocus_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
-    | ([], [], [], `FocusTag) :: s -> s
-    | _ -> fail (lazy "can't unfocus, some goals are still open")
+    | (g, [], [], `FocusTag) :: s when filter_open g = [] -> s
+    | _ as s -> fail (lazy ("can't unfocus, some goals are still open:\n"^
+      Continuationals.Stack.pp s))
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let skip_tac status =
-  let new_gstatus = 
-    match status.gstatus with
+  let gstatus = 
+    match status#stack with
     | [] -> assert false
     | (gl, t, k, tag) :: s -> 
         let gl = List.map switch_of_loc gl in
@@ -146,23 +172,19 @@ let skip_tac status =
         else 
           ([],t,k,tag) :: s
   in
-   { status with gstatus = new_gstatus }
+   status#set_stack gstatus
 ;;
 
 let block_tac l status =
   List.fold_left (fun status tac -> tac status) status l
 ;;
 
+
 let compare_statuses ~past ~present =
- let _,_,past,_,_ = past.pstatus in 
- let _,_,present,_,_ = present.pstatus in 
- let closed = 
-  List.map fst (List.filter (fun (i,_) -> not (List.mem_assoc i present)) past)
- in
- let opened = 
-   List.map fst (List.filter (fun (i,_) -> not(List.mem_assoc i past)) present)
- in
- opened, closed
+ let _,_,past,_,_ = past#obj in 
+ let _,_,present,_,_ = present#obj in 
+ List.map fst (List.filter (fun (i,_) -> not(List.mem_assoc i past)) present),
+ List.map fst (List.filter (fun (i,_) -> not (List.mem_assoc i present)) past)
 ;;
 
 
@@ -180,14 +202,17 @@ let compare_statuses ~past ~present =
    (e.g. the tactic could perform a global analysis of the set of goals)
 *)
 
-let exec tac low_status g =
+let exec tac (low_status : #lowtac_status) g =
   let stack = [ [0,Open g], [], [], `NoTag ] in
-  let status = tac { gstatus = stack ; istatus = low_status } in
-   status.istatus
+  let status =
+   (new NTacStatus.status low_status#obj stack)#set_estatus low_status
+  in
+  let status = tac status in
+   (low_status#set_estatus status)#set_obj status#obj
 ;;
 
-let distribute_tac tac status =
-  match status.gstatus with
+let distribute_tac tac (status : #tac_status) =
+  match status#stack with
   | [] -> assert false
   | (g, t, k, tag) :: s ->
       debug_print (lazy ("context length " ^string_of_int (List.length g)));
@@ -211,7 +236,8 @@ let distribute_tac tac status =
             in
             aux s go gc loc_tl
       in
-      let s0, go0, gc0 = status.istatus, [], [] in
+      let s0 = (new NTacStatus.status status#obj ())#set_estatus status in
+      let s0, go0, gc0 = s0, [], [] in
       let sn, gon, gcn = aux s0 go0 gc0 g in
       debug_print (lazy ("opened: "
         ^ String.concat " " (List.map string_of_int gon)));
@@ -220,18 +246,51 @@ let distribute_tac tac status =
       let stack =
         (zero_pos gon, t @~- gcn, k @~- gcn, tag) :: deep_close gcn s
       in
-       { gstatus = stack; istatus = sn }
+       ((status#set_stack stack)#set_obj(sn:>lowtac_status)#obj)#set_estatus sn
 ;;
 
-let atomic_tac htac = distribute_tac (exec htac) ;;
+let atomic_tac htac : #tac_status as 'a -> 'a = distribute_tac (exec htac) ;;
 
-let exact t status goal =
- let goalty = get_goalty status goal in
- let status, t = disambiguate status t (Some goalty) (ctx_of goalty) in
- instantiate status goal t
+let repeat_tac t s = 
+  let rec repeat t (status : #tac_status as 'a) : 'a = 
+    try repeat t (t status)
+    with NTacStatus.Error _ -> status
+  in
+    atomic_tac (repeat t) s
 ;;
 
-let exact_tac t = distribute_tac (exact t) ;;
+
+let try_tac tac status =
+  try
+    tac status
+  with NTacStatus.Error _ ->
+    status
+;;
+
+let first_tac tacl status =
+  let res = 
+   HExtlib.list_findopt
+    (fun tac _ -> try Some (tac status) with NTacStatus.Error _ -> None) tacl
+  in
+    match res with
+      | None -> fail (lazy "No tactics left")
+      | Some x -> x
+;;
+
+let exact_tac t : 's tactic = distribute_tac (fun status goal ->
+ instantiate_with_ast status goal t)
+;;
+
+let assumption_tac status = distribute_tac (fun status goal ->
+  let gty = get_goalty status goal in
+  let context = ctx_of gty in
+  let htac = 
+   first_tac
+    (List.map (fun (name,_) -> exact_tac ("",0,(Ast.Ident (name,None))))
+      context)
+  in
+    exec htac status goal) status
+;;
 
 let find_in_context name context =
   let rec aux acc = function
@@ -242,48 +301,75 @@ let find_in_context name context =
   aux 1 context
 ;;
 
-let clear names status goal =
- let goalty = get_goalty status goal in
- let js =
-   List.map 
+let clear_tac names =
+ if names = [] then id_tac
+ else
+  distribute_tac (fun status goal ->
+   let goalty = get_goalty status goal in
+   let js =
+     List.map 
      (fun name -> 
         try find_in_context name (ctx_of goalty)
         with Not_found -> 
           fail (lazy ("hypothesis '" ^ name ^ "' not found"))) 
      names
- in
- let n,h,metasenv,subst,o = status.pstatus in
- let metasenv,subst,_ = NCicMetaSubst.restrict metasenv subst goal js in
-  { status with pstatus = n,h,metasenv,subst,o }
-;;
-
-let force f s = Lazy.force f s;;
-
-let clear_tac names =
- if names = [] then id_tac else distribute_tac (clear names)
+   in
+   let n,h,metasenv,subst,o = status#obj in
+   let metasenv,subst,_,_ = NCicMetaSubst.restrict metasenv subst goal js in
+    status#set_obj (n,h,metasenv,subst,o))
 ;;
 
 let generalize0_tac args =
  if args = [] then id_tac
- else exact_tac ("",0,Ast.Appl (Ast.Implicit :: args))
+ else exact_tac ("",0,Ast.Appl (Ast.Implicit `JustOne :: args))
 ;;
 
-let select0_tac ~where:(wanted,_,where) ~job  =
+let select0_tac ~where:(wanted,hyps,where) ~job  =
  let found, postprocess = 
    match job with
    | `Substexpand argsno -> mk_in_scope, mk_out_scope argsno
    | `Collect l -> (fun s t -> l := t::!l; mk_in_scope s t), mk_out_scope 1
+   | `ChangeWith f -> f,(fun s t -> s, t)
  in
  distribute_tac (fun status goal ->
    let goalty = get_goalty status goal in
    let path = 
      match where with None -> NCic.Implicit `Term | Some where -> where 
    in
-   let status, newgoalty = 
-     select_term status ~found ~postprocess goalty (wanted,path) 
+   let status, newgoalctx =
+      List.fold_right
+       (fun (name,d as entry) (status,ctx) ->
+         try
+          let path = List.assoc name hyps in
+           match d with
+              NCic.Decl ty ->
+               let status,ty =
+                select_term status ~found ~postprocess (mk_cic_term ctx ty)
+                 (wanted,path) in
+               let status,ty = term_of_cic_term status ty ctx in
+                status,(name,NCic.Decl ty)::ctx
+            | NCic.Def (bo,ty) ->
+               let status,bo =
+                select_term status ~found ~postprocess (mk_cic_term ctx bo)
+                 (wanted,path) in
+               let status,bo = term_of_cic_term status bo ctx in
+                status,(name,NCic.Def (bo,ty))::ctx
+         with
+          Not_found -> status, entry::ctx
+       ) (ctx_of goalty) (status,[])
    in
+   let status, newgoalty = 
+     select_term status ~found ~postprocess goalty (wanted,path) in
+   (* WARNING: the next two lines simply change the context of newgoalty
+      from the old to the new one. Otherwise mk_meta will do that herself,
+      calling relocate that calls delift. However, newgoalty is now
+      ?[out_scope] and thus the delift would trigger the special unification
+      case, which is wrong now :-( *)
+   let status,newgoalty = term_of_cic_term status newgoalty (ctx_of goalty) in
+   let newgoalty = mk_cic_term newgoalctx newgoalty in
+
    let status, instance = 
-     mk_meta status (ctx_of newgoalty) (`Decl newgoalty) 
+     mk_meta status newgoalctx (`Decl newgoalty) `IsTerm
    in
    instantiate status goal instance)
 ;;
@@ -310,66 +396,78 @@ let generalize_tac ~where =
  let l = ref [] in
  block_tac [ 
    select_tac ~where ~job:(`Collect l) true; 
-   force (lazy (distribute_tac (fun status goal ->
-     let goalty = get_goalty status goal in
-     (* unift (ctx_of goal) t s *)
-     instantiate status goal 
-       (mk_cic_term (ctx_of goalty) (NCic.Appl [NCic.Implicit `Term ; 
-         term_of_cic_term (List.hd !l) (ctx_of goalty) ]))
-   ))) ]
-;;
-
-
-let reopen status =
- let n,h,metasenv,subst,o = status.pstatus in
- let subst, newm = 
-   List.partition 
-    (function (_,(Some tag,_,_,_)) -> 
-            tag <> NCicMetaSubst.in_scope_tag && 
-            not (NCicMetaSubst.is_out_scope_tag tag)
-    | _ -> true)
-    subst 
- in
- let in_m, out_m = 
-   List.partition
-     (function (_,(Some tag,_,_,_)) -> 
-         tag = NCicMetaSubst.in_scope_tag | _ -> assert false)
-     newm
- in
- let metasenv = List.map (fun (i,(_,c,_,t)) -> i,(None,c,t)) in_m @ metasenv in
- let in_m = List.map fst in_m in
- let out_m = match out_m with [i] -> i | _ -> assert false in
- { status with pstatus = n,h,metasenv,subst,o }, in_m, out_m 
+   (fun s -> distribute_tac (fun status goal ->
+      let goalty = get_goalty status goal in
+      let status,canon,rest =
+       match !l with
+          [] ->
+           (match where with
+               _,_,(None,_,_)  -> fail (lazy "No term to generalize")
+             | txt,txtlen,(Some what,_,_) ->
+                let status, what =
+                 disambiguate status (ctx_of goalty) (txt,txtlen,what) None
+                in
+                 status,what,[]
+           )
+        | he::tl -> status,he,tl in
+      let status = 
+       List.fold_left 
+         (fun s t -> unify s (ctx_of goalty) canon t) status rest in
+      let status, canon = term_of_cic_term status canon (ctx_of goalty) in
+      instantiate status goal 
+       (mk_cic_term (ctx_of goalty) (NCic.Appl [NCic.Implicit `Term ; canon ]))
+   ) s) ]
 ;;
 
-let change ~where ~with_what status goal =
- let goalty = get_goalty status goal in
- let (wanted,_,where) = GrafiteDisambiguate.disambiguate_npattern where in
- let path = 
-   match where with None -> NCic.Implicit `Term | Some where -> where 
- in
- let status, newgoalty = assert false (*
-   select_term status 1 goalty (wanted,path)*) in
- let status, in_scope, out_scope = reopen status in
- let status =  List.fold_left (exact with_what) status in_scope in
+let cut_tac t = 
+ block_tac [ 
+  exact_tac ("",0, Ast.Appl [Ast.Implicit `JustOne; Ast.Implicit `JustOne]);
+  branch_tac;
+   pos_tac [3]; exact_tac t;
+   shift_tac; pos_tac [2]; skip_tac;
+  merge_tac ]
+;;
 
- let j,(n,cctx,bo,_) = out_scope in
- let _ = typeof status (ctx_of goalty) (Obj.magic (n,cctx,bo))  in
+let lapply_tac (s,n,t) = 
+ exact_tac (s,n, Ast.Appl [Ast.Implicit `JustOne; t])
+;;
 
- let n,h,metasenv,subst,o = status.pstatus in
- let subst = out_scope :: subst in
- let status = { status with pstatus = n,h,metasenv,subst,o } in
+let reduce_tac ~reduction ~where =
+  let change status t = 
+    match reduction with
+    | `Normalize perform_delta ->
+        normalize status
+         ?delta:(if perform_delta then None else Some max_int) (ctx_of t) t
+    | `Whd perform_delta -> 
+        whd status
+         ?delta:(if perform_delta then None else Some max_int) (ctx_of t) t
+  in
+  let where = GrafiteDisambiguate.disambiguate_npattern where in
+  select0_tac ~where ~job:(`ChangeWith change)
+;;
 
- let status, instance = 
-   mk_meta status (ctx_of newgoalty) (`Decl newgoalty) 
- in
- instantiate status goal instance
+let change_tac ~where ~with_what =
+  let change status t = 
+    let status, ww = disambiguate status (ctx_of t) with_what  None in
+    let status = unify status (ctx_of t) t ww in
+    status, ww
+  in
+  let where = GrafiteDisambiguate.disambiguate_npattern where in
+  select0_tac ~where ~job:(`ChangeWith change)
 ;;
 
-let apply t status goal = exact t status goal;;
+let letin_tac ~where ~what:(_,_,w) name =
+ block_tac [
+  select_tac ~where ~job:(`Substexpand 1) true;
+  exact_tac
+   ("",0,Ast.LetIn((Ast.Ident (name,None),None),w,Ast.Implicit `JustOne));
+ ]
+;;
 
-let apply_tac t = distribute_tac (apply t) ;;
-let change_tac ~where ~with_what = distribute_tac (change ~where ~with_what) ;;
+let apply_tac (s,n,t) = 
+  let t = Ast.Appl [t; Ast.Implicit `Vector] in
+  exact_tac (s,n,t)
+;;
 
 type indtyinfo = {
         rightno: int;
@@ -381,98 +479,104 @@ type indtyinfo = {
  }
 ;;
 
-let analyze_indty_tac ~what indtyref = distribute_tac (fun status goal ->
+let ref_of_indtyinfo iti = iti.reference;;
+
+let analyze_indty_tac ~what indtyref =
+ distribute_tac (fun status goal ->
   let goalty = get_goalty status goal in
-  let status, what = disambiguate status what None (ctx_of goalty) in
-  let ty_what = typeof status (ctx_of what) what in 
-  let r,consno,lefts,rights = analyse_indty status ty_what in
-  let leftno = List.length rights in
+  let status, what = disambiguate status (ctx_of goalty) what None in
+  let status, ty_what = typeof status (ctx_of what) what in 
+  let status, (r,consno,lefts,rights) = analyse_indty status ty_what in
+  let leftno = List.length lefts in
   let rightno = List.length rights in
   indtyref := Some { 
     rightno = rightno; leftno = leftno; consno = consno;
     lefts = lefts; rights = rights; reference = r;
   };
-  prerr_endline "FO";
   exec id_tac status goal)
 ;;
 
-let elim_tac ~what ~where = 
+let sort_of_goal_tac sortref = distribute_tac (fun status goal ->
+  let goalty = get_goalty status goal in
+  let status,sort = typeof status (ctx_of goalty) goalty in
+  let status, sort = fix_sorts status sort in
+  let status, sort = term_of_cic_term status sort (ctx_of goalty) in
+   sortref := sort;
+   status)
+;;
+
+let elim_tac ~what:(txt,len,what) ~where = 
+  let what = txt, len, Ast.Appl [what; Ast.Implicit `Vector] in
   let indtyinfo = ref None in
-  let sort = ref None in
-  let compute_goal_sort_tac = distribute_tac (fun status goal ->
-    let goalty = get_goalty status goal in
-    let goalsort = typeof status (ctx_of goalty) goalty in
-    prerr_endline "XXXXXXXX";
-    sort := Some goalsort;
-    exec id_tac status goal)
-  in
+  let sort = ref (NCic.Rel 1) in
   atomic_tac (block_tac [
     analyze_indty_tac ~what indtyinfo;    
-    force (lazy (select_tac 
-      ~where ~job:(`Substexpand ((HExtlib.unopt !indtyinfo).rightno+1)) true));
-    print_tac "CIAO";
-    compute_goal_sort_tac;
-    print_tac "CIAO2";
-    force (lazy (
-     let sort = HExtlib.unopt !sort in
+    (fun s -> select_tac 
+      ~where ~job:(`Substexpand ((HExtlib.unopt !indtyinfo).rightno+1)) true s);
+    sort_of_goal_tac sort;
+    (fun status ->
      let ity = HExtlib.unopt !indtyinfo in
      let NReference.Ref (uri, _) = ity.reference in
-     let name = NUri.name_of_uri uri ^
-      match term_of_cic_term sort (ctx_of sort) with
-       | NCic.Sort NCic.Prop -> "_ind"
-       | NCic.Sort _ -> "_rect"
-       | _ -> assert false 
+     let name = 
+       NUri.name_of_uri uri ^ "_" ^
+        snd (NCicElim.ast_of_sort 
+          (match !sort with NCic.Sort x -> x | _ -> assert false))
      in
-     let holes = 
-       HExtlib.mk_list Ast.Implicit (ity.leftno+1+ ity.consno + ity.rightno) in
      let eliminator = 
        let _,_,w = what in
-       Ast.Appl(Ast.Ident(name,None)::holes @ [ w ])
+       Ast.Appl [ Ast.Ident (name,None) ; Ast.Implicit `Vector ; w ]
      in
-     exact_tac ("",0,eliminator))) ]) 
+     exact_tac ("",0,eliminator) status) ]) 
 ;;
 
-let rewrite_tac ~dir ~what:(_,_,what) ~where =
+let rewrite_tac ~dir ~what:(_,_,what) ~where status =
+ let sortref = ref (NCic.Rel 1) in
+ let status = sort_of_goal_tac sortref status in
+ let suffix = "_" ^ snd (NCicElim.ast_of_sort 
+   (match !sortref with NCic.Sort x -> x | _ -> assert false))
+ in
  let name =
-  match dir with `LeftToRight -> "eq_elim_r" | `RightToLeft -> "eq_ind"
+  match dir with
+     `LeftToRight -> "eq" ^ suffix ^ "_r"
+   | `RightToLeft -> "eq" ^ suffix
  in
   block_tac
-   [ select_tac ~where ~job:(`Substexpand 2) true;
+   [ select_tac ~where ~job:(`Substexpand 1) true;
      exact_tac
       ("",0,
-       Ast.Appl(Ast.Ident(name,None)::HExtlib.mk_list Ast.Implicit 5 @
-        [what]))]
+       Ast.Appl(Ast.Ident(name,None)::HExtlib.mk_list (Ast.Implicit `JustOne) 5@
+        [what]))] status
 ;;
 
 let intro_tac name =
  block_tac
   [ exact_tac
-    ("",0,(Ast.Binder (`Lambda,
-     (Ast.Ident (name,None),None),Ast.Implicit)));
-     if name = "_" then clear_tac [name] else id_tac ]
+     ("",0,(Ast.Binder (`Lambda,
+      (Ast.Ident (name,None),None),Ast.Implicit `JustOne)));
+    if name = "_" then clear_tac [name] else id_tac ]
 ;;
 
 let cases ~what status goal =
  let gty = get_goalty status goal in
- let status, what = disambiguate status what None (ctx_of gty) in
- let ty = typeof status (ctx_of what) what in
- let ref, consno, _, _ = analyse_indty status ty in
+ let status, what = disambiguate status (ctx_of gty) what None in
+ let status, ty = typeof status (ctx_of what) what in
+ let status, (ref, consno, _, _) = analyse_indty status ty in
+ let status, what = term_of_cic_term status what (ctx_of gty) in
  let t =
-  NCic.Match (ref,NCic.Implicit `Term, term_of_cic_term what (ctx_of gty),
+  NCic.Match (ref,NCic.Implicit `Term, what,
     HExtlib.mk_list (NCic.Implicit `Term) consno)
  in
- let ctx = ctx_of gty in
- let status,t,ty = refine status ctx (mk_cic_term ctx t) (Some gty) in
- instantiate status goal t
+ instantiate status goal (mk_cic_term (ctx_of gty) t)
 ;;
 
-let cases_tac ~what ~where = 
+let cases_tac ~what:(txt,len,what) ~where = 
+  let what = txt, len, Ast.Appl [what; Ast.Implicit `Vector] in
   let indtyinfo = ref None in
   atomic_tac 
    (block_tac [
       analyze_indty_tac ~what indtyinfo;
-      force (lazy (select_tac 
-        ~where ~job:(`Substexpand ((HExtlib.unopt !indtyinfo).rightno+1))true));
+      (fun s -> select_tac 
+       ~where ~job:(`Substexpand ((HExtlib.unopt !indtyinfo).rightno+1))true s);
       distribute_tac (cases ~what) ])
 ;;
 
@@ -482,5 +586,69 @@ let case1_tac name =
              cases_tac 
               ~where:("",0,(None,[],None)) 
               ~what:("",0,Ast.Ident (name,None));
-              if name = "_clearme" then clear_tac ["_clearme"] else id_tac ]
+             if name = "_clearme" then clear_tac ["_clearme"] else id_tac ]
 ;;
+
+let constructor_tac ?(num=1) ~args = distribute_tac (fun status goal ->
+  if num < 1 then fail (lazy "constructor numbers begin with 1");
+  let gty = get_goalty status goal in
+  let status, (r,_,_,_) = analyse_indty status gty in
+  let ref = NReference.mk_constructor num r in
+  let t = 
+    if args = [] then Ast.NRef ref else
+    Ast.Appl (HExtlib.list_concat ~sep:[Ast.Implicit `Vector]
+      ([Ast.NRef ref] :: List.map (fun _,_,x -> [x]) args))
+  in
+  exec (apply_tac ("",0,t)) status goal)
+;;
+
+let assert0_tac (hyps,concl) = distribute_tac (fun status goal ->
+ let gty = get_goalty status goal in
+ let eq status ctx t1 t2 =
+  let status,t1 = disambiguate status ctx t1 None in
+  let status,t1 = apply_subst status ctx t1 in
+  let status,t1 = term_of_cic_term status t1 ctx in
+  let t2 = mk_cic_term ctx t2 in
+  let status,t2 = apply_subst status ctx t2 in
+  let status,t2 = term_of_cic_term status t2 ctx in
+  prerr_endline ("COMPARING: " ^ NCicPp.ppterm ~subst:[] ~metasenv:[] ~context:ctx t1 ^ " vs " ^ NCicPp.ppterm ~subst:[] ~metasenv:[] ~context:ctx t2);
+  assert (t1=t2);
+  status
+ in
+ let status,gty' = term_of_cic_term status gty (ctx_of gty) in
+ let status = eq status (ctx_of gty) concl gty' in
+ let status,_ =
+  List.fold_right2
+   (fun (id1,e1) ((id2,e2) as item) (status,ctx) ->
+     assert (id1=id2 || (prerr_endline (id1 ^ " vs " ^ id2); false));
+     match e1,e2 with
+        `Decl t1, NCic.Decl t2 ->
+          let status = eq status ctx t1 t2 in
+          status,item::ctx
+      | `Def (b1,t1), NCic.Def (b2,t2) ->
+          let status = eq status ctx t1 t2 in
+          let status = eq status ctx b1 b2 in
+          status,item::ctx
+      | _ -> assert false
+   ) hyps (ctx_of gty) (status,[])
+ in
+  exec id_tac status goal)
+;;
+
+let assert_tac seqs status =
+ match status#stack with
+  | [] -> assert false
+  | (g,_,_,_) :: s ->
+     assert (List.length g = List.length seqs);
+     (match seqs with
+         [] -> id_tac
+       | [seq] -> assert0_tac seq
+       | _ ->
+         block_tac
+          ((branch_tac ~force:false)::
+          HExtlib.list_concat ~sep:[shift_tac]
+            (List.map (fun seq -> [assert0_tac seq]) seqs)@
+          [merge_tac])
+     ) status
+;;
+