X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fextlib%2FhExtlib.ml;h=3ef795e9fca4badc9299cd2a0f4207fe1af2afa5;hb=6b3242efcd29ea188ef09b445985abb06c5fad3a;hp=3fe5c0a7d40762ba0340a82ddad0dc685ee1c44c;hpb=8d58fba703fcb1cfddd2a78a0b157a087bcf2a5b;p=helm.git

diff --git a/helm/software/components/extlib/hExtlib.ml b/helm/software/components/extlib/hExtlib.ml
index 3fe5c0a7d..3ef795e9f 100644
--- a/helm/software/components/extlib/hExtlib.ml
+++ b/helm/software/components/extlib/hExtlib.ml
@@ -148,6 +148,16 @@ let list_mapi f l =
      aux 0 l
 ;;
 
+let list_index p =
+ let rec aux n =
+  function
+     [] -> None
+   | he::_ when p he -> Some (n,he)
+   | _::tl -> aux (n + 1) tl
+ in
+  aux 0
+;;
+
 let rec list_iter_default2 f l1 def l2 = 
   match l1,l2 with
     | [], _ -> ()
@@ -239,14 +249,14 @@ 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 =