From: Rob Hoes <rob.hoes@citrix.com>
Date: Wed, 17 Feb 2010 10:14:31 +0000 (+0000)
Subject: CP-1622: Listext function to replace the value for a key in an assoc list
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=7116aeedecf657e672343fdd84b99e02d7d403db;p=xcp%2Fxen-api-libs.git

CP-1622: Listext function to replace the value for a key in an assoc list

Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
---

diff --git a/stdext/listext.ml b/stdext/listext.ml
index 29ad0ee..9023569 100644
--- a/stdext/listext.ml
+++ b/stdext/listext.ml
@@ -192,4 +192,13 @@ let take n list =
 let rec tails = function
     | [] -> [[]]
     | (_::xs) as l -> l :: tails xs
+
+let rec replace_assoc key new_value = function
+	| [] -> []
+	| (k, _) as p :: tl ->
+		if k = key then
+			(key, new_value) :: tl
+		else
+			p :: replace_assoc key new_value tl
+
 end
diff --git a/stdext/listext.mli b/stdext/listext.mli
index c8b4ced..d1f8b1e 100644
--- a/stdext/listext.mli
+++ b/stdext/listext.mli
@@ -177,4 +177,6 @@ module List :
 	
     val tails : 'a list -> ('a list) list
 
+	(** Replace the value belonging to a key in an association list. *)
+	val replace_assoc : 'a -> 'b -> ('a * 'b) list -> ('a * 'b) list
   end