X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=ocaml%2Fnum.ml;h=8ecf12491be1d9931dfdc39fbbe4c9403f391008;hb=276d4f75cbe40801f2d9faa82ac82d1c82204e55;hp=66bdd8598f0d3ced253a46bce4d66ac2088080bd;hpb=9ad3734756bdab9ea23884a7bddbfaa599dbd3ae;p=fireball-separation.git

diff --git a/ocaml/num.ml b/ocaml/num.ml
index 66bdd85..8ecf124 100644
--- a/ocaml/num.ml
+++ b/ocaml/num.ml
@@ -92,14 +92,23 @@ let free_vars = (List.map fst) ++ free_vars';;
 module ToScott =
 struct
 
+let delta = let open Pure in L(A(V 0, V 0))
+
+let bomb = ref(`Var(-1, -666));;
+
 let rec t_of_i_num_var =
  function
   | `N n -> Scott.mk_n n
-  | `Var(v,_) -> Pure.V v
+  | `Var(v,_) as x -> assert (x <> !bomb); Pure.V v
   | `Match(t,_,liftno,bs,args) ->
-      let bs = List.map (fun (n,t) -> n, t_of_nf (lift liftno t)) !bs in
+      let bs = List.map (
+        function (n,t) -> n,
+         (if t = !bomb then delta
+          else L (t_of_nf (lift (liftno+1) t)))
+        ) !bs in
       let t = t_of_i_num_var t in
       let m = Scott.mk_match t bs in
+      let m = Pure.A(m,delta) in
       List.fold_left (fun acc t -> Pure.A(acc,t_of_nf t)) m args
   | `I((v,_), args) -> Listx.fold_left (fun acc t -> Pure.A(acc,t_of_nf t)) (Pure.V v) args
 and t_of_nf =
@@ -118,7 +127,7 @@ let rec string_of_term =
  let boundvar x = "v" ^ string_of_int x in
  let varname lev l n =
   if n < lev then boundvar (lev-n-1)
-   else if n < List.length l then List.nth l (n-lev)
+   else if n - lev < List.length l then List.nth l (n-lev)
     else "`" ^ string_of_int (n-lev) in
  let rec string_of_term_w_pars lev l  = function
   | `Var(n,ar) -> varname lev l n ^ (if debug_display_arities then ":" ^ string_of_int ar else "")