- hExtlib: added debugging information for split_nth

[helm.git] / helm / software / components / ng_kernel / nCicReduction.ml

diff --git a/helm/software/components/ng_kernel/nCicReduction.ml b/helm/software/components/ng_kernel/nCicReduction.ml
index 8012f0b753990745d037e3ee0a4d678f1f6c4398..aa7f84ad660428a9109e47fcf02fc97a81365f24 100644 (file)
--- a/helm/software/components/ng_kernel/nCicReduction.ml
+++ b/helm/software/components/ng_kernel/nCicReduction.ml
@@ -15,6 +15,8 @@ module C = NCic
 module Ref = NReference
 module E = NCicEnvironment
 
+exception AssertFailure of string Lazy.t;;
+
 module type Strategy = sig
   type stack_term
   type env_term
@@ -162,7 +164,7 @@ module Reduction(RS : Strategy) = struct
         | (_, _, C.Const (Ref.Ref (_,Ref.Con (_,j,_))),[]) ->
             aux (k, e, List.nth pl (j-1), s)
         | (_, _, C.Const (Ref.Ref (_,Ref.Con (_,j,lno))), s')->
-          let _,params = HExtlib.split_nth lno s' in
+          let _,params = HExtlib.split_nth "NR 1" lno s' in
           aux (k, e, List.nth pl (j-1), params@s)
         | _ -> config, true)
    in
@@ -251,7 +253,7 @@ let are_convertible ~metasenv ~subst =
          let relevance = E.get_relevance r1 in
          let relevance = match r1 with
              | Ref.Ref (_,Ref.Con (_,_,lno)) ->
-                 let _,relevance = HExtlib.split_nth lno relevance in
+                 let _,relevance = HExtlib.split_nth "NR 2" lno relevance in
                    HExtlib.mk_list false lno @ relevance
              | _ -> relevance
          in
@@ -263,13 +265,13 @@ let are_convertible ~metasenv ~subst =
               | HExtlib.FailureAt fail ->
                 let relevance = 
                    !get_relevance ~metasenv ~subst context hd1 tl1 in
-                let _,relevance = HExtlib.split_nth fail relevance in
+                let _,relevance = HExtlib.split_nth "NR 3" fail relevance in
                 let b,relevance = (match relevance with
                   | [] -> assert false
                   | b::tl -> b,tl) in
                 if (not b) then
-                  let _,tl1 = HExtlib.split_nth (fail+1) tl1 in
-                  let _,tl2 = HExtlib.split_nth (fail+1) tl2 in
+                  let _,tl1 = HExtlib.split_nth "NR 4" (fail+1) tl1 in
+                  let _,tl2 = HExtlib.split_nth "NR 5" (fail+1) tl2 in
                     try
                         HExtlib.list_forall_default3
                         (fun t1 t2 b -> not b || aux true context t1 t2)
@@ -363,24 +365,32 @@ let are_convertible ~metasenv ~subst =
   aux false 
 ;;
 
-let rec head_beta_reduce ?(delta=max_int) ?(upto=(-1)) t l =
+let rec head_beta_reduce ~delta ~upto ~subst t l =
  match upto, t, l with
   | 0, C.Appl l1, _ -> C.Appl (l1 @ l)
   | 0, t, [] -> t
   | 0, t, _ -> C.Appl (t::l)
-  | _, C.Appl (hd::tl), _ -> head_beta_reduce ~delta ~upto hd (tl @ l)
+  | _, C.Meta (n,ctx), _ ->
+     (try
+       let _,_, term,_ = NCicUtils.lookup_subst n subst in
+       head_beta_reduce ~delta ~upto ~subst 
+         (NCicSubstitution.subst_meta ctx term) l
+     with NCicUtils.Subst_not_found _ -> if l = [] then t else C.Appl (t::l))
+  | _, C.Appl (hd::tl), _ -> head_beta_reduce ~delta ~upto ~subst hd (tl @ l)
   | _, C.Lambda(_,_,bo), arg::tl ->
      let bo = NCicSubstitution.subst arg bo in
-     head_beta_reduce ~delta ~upto:(upto - 1) bo tl
+     head_beta_reduce ~delta ~upto:(upto - 1) ~subst bo tl
   | _, C.Const (Ref.Ref (_, Ref.Def height) as re), _ 
     when delta <= height ->
       let _, _, bo, _, _, _ = NCicEnvironment.get_checked_def re in
-      head_beta_reduce ~upto ~delta bo l
+      head_beta_reduce ~upto ~delta ~subst bo l
   | _, t, [] -> t
   | _, t, _ -> C.Appl (t::l)
 ;;
 
-let head_beta_reduce ?delta ?upto t = head_beta_reduce ?delta ?upto t [];;
+let head_beta_reduce ?(delta=max_int) ?(upto= -1) ?(subst=[]) t = 
+  head_beta_reduce ~delta ~upto ~subst t []
+;;
 
 type stack_item = RS.stack_term
 type environment_item = RS.env_term
@@ -391,4 +401,19 @@ let reduce_machine = R.reduce
 let from_stack = RS.from_stack
 let unwind = R.unwind
 
+let _ = 
+  NCicUtils.set_head_beta_reduce (fun ~upto t -> head_beta_reduce ~upto t);
+  NCicPp.set_head_beta_reduce (fun ~upto t -> head_beta_reduce ~upto t);
+;;
+
+(* if n < 0, then splits all prods from an arity, returning a sort *)
+let rec split_prods ~subst context n te =
+  match (n, R.whd ~subst context te) with
+   | (0, _) -> context,te
+   | (n, C.Sort _) when n <= 0 -> context,te
+   | (n, C.Prod (name,so,ta)) ->
+       split_prods ~subst ((name,(C.Decl so))::context) (n - 1) ta
+   | (_, _) -> raise (AssertFailure (lazy "split_prods"))
+;;
+
 (* vim:set foldmethod=marker: *)