X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fextlib%2FhExtlib.ml;h=523913cbfcda4e6e2e501103d068d1462ff9232e;hb=ee242468b221c64b25c99b52110fe00380f4eebe;hp=fe0f417cdf88521a401a54d0ebbf41ba79ef0b58;hpb=ff5d621723a60609c67152c110b8386f7902c1ff;p=helm.git

diff --git a/helm/software/components/extlib/hExtlib.ml b/helm/software/components/extlib/hExtlib.ml
index fe0f417cd..523913cbf 100644
--- a/helm/software/components/extlib/hExtlib.ml
+++ b/helm/software/components/extlib/hExtlib.ml
@@ -164,6 +164,23 @@ let rec list_forall_default3 f l1 l2 def l3 =
     | a::ta, b::tb, [] -> f a b def && list_forall_default3 f ta tb def [] 
 ;;
 
+exception FailureAt of int;;
+
+let list_forall_default3_var f l1 l2 def l3 = 
+  let rec aux f l1 l2 def l3 i =
+    match l1,l2,l3 with
+      | [], [], _ -> true
+      | [], _, _
+      | _, [], _ -> raise (Invalid_argument "list_forall_default3")
+      | a::ta, b::tb, c::tc -> 
+      	  if f a b c then aux f ta tb def tc (i+1)
+	  else raise (FailureAt i)
+      | a::ta, b::tb, [] ->
+      	  if f a b def then aux f ta tb def [] (i+1)
+	  else raise (FailureAt i)
+  in aux f l1 l2 def l3 0
+;;
+
 let sharing_map f l =
   let unchanged = ref true in
   let rec aux b = function
@@ -222,14 +239,14 @@ let list_concat ?(sep = []) =
   aux []
   
 let rec list_findopt f l = 
-  let rec aux = function 
+  let rec aux k = function 
     | [] -> None 
     | x::tl -> 
-        (match f x with
-        | None -> aux tl
+        (match f x k with
+        | None -> aux (succ k) tl
         | Some _ as rc -> rc)
   in
-  aux l
+  aux 0 l
 
 let split_nth n l =
   let rec aux acc n l =
@@ -447,7 +464,7 @@ let loc_of_floc floc = Stdpp.first_pos floc, Stdpp.last_pos floc;;
 let floc_of_loc (loc_begin, loc_end) =
  Stdpp.make_loc (loc_begin, loc_end)
 
-let dummy_floc = floc_of_loc (-1, -1)
+let dummy_floc = floc_of_loc (0, 0)
 
 let raise_localized_exception ~offset floc exn =
  let x, y = loc_of_floc floc in
@@ -522,6 +539,7 @@ let rec mk_list x = function
 ;;
 
 let list_seq start stop =
+  if start > stop then [] else
   let rec aux pos =
     if pos = stop then []
     else pos :: (aux (pos+1))
@@ -529,3 +547,10 @@ let list_seq start stop =
     aux start
 ;;
 
+let rec list_skip n l =
+  match n,l with
+  | 0,_ -> l
+  | n,_::l -> list_skip (n-1) l
+  | _, [] -> assert false
+;;
+