symmetry of inequality sym_neq

[helm.git] / helm / software / components / extlib / hExtlib.ml

diff --git a/helm/software/components/extlib/hExtlib.ml b/helm/software/components/extlib/hExtlib.ml
index 3fe5c0a7d40762ba0340a82ddad0dc685ee1c44c..5f2c7f78caab9eef51dc733ebe59d4addfee1194 100644 (file)
--- 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 =
@@ -260,7 +270,13 @@ let list_last l =
   let l = List.rev l in 
   try List.hd l with exn -> raise (Failure "HExtlib.list_last")
 ;;
-  
+
+let rec list_assoc_all a = function
+   | []                      -> []
+   | (x, y) :: tl when x = a -> y :: list_assoc_all a tl
+   | _ :: tl                 -> list_assoc_all a tl
+;;
+
 (** {2 File predicates} *)
 
 let is_dir fname =