diff --git a/core/CCKList.ml b/core/CCKList.ml
index 95809eaf..f59ea6ad 100644
--- a/core/CCKList.ml
+++ b/core/CCKList.ml
@@ -34,6 +34,8 @@ type + 'a t =
 let nil = `Nil
 let cons a b = `Cons (a,b)
 
+let singleton x = `Cons (x, fun () -> `Nil)
+
 let to_list l =
   let rec direct i (l:'a t) = match l with
     | `Nil -> []
@@ -45,6 +47,12 @@ let to_list l =
   in
   direct 200 l
 
+let of_list l =
+  let rec aux l () = match l with
+    | [] -> `Nil
+    | x::l' -> `Cons (x, aux l')
+  in aux l ()
+
 type 'a sequence = ('a -> unit) -> unit
 type 'a gen = unit -> 'a option
 
@@ -65,6 +73,10 @@ let rec fold f acc res = match res with
   | `Nil -> acc
   | `Cons (s, cont) -> fold f (f acc s) (cont ())
 
+let rec iter f l = match l with
+  | `Nil -> ()
+  | `Cons (x, l') -> f x; iter f (l' ())
+
 let length l = fold (fun acc _ -> acc+1) 0 l
 
 let rec take n (l:'a t):'a t = match l with
diff --git a/core/CCKList.mli b/core/CCKList.mli
index 7ed21cd2..cb568e27 100644
--- a/core/CCKList.mli
+++ b/core/CCKList.mli
@@ -34,8 +34,12 @@ val nil : 'a t
 
 val cons : 'a -> (unit -> 'a t) -> 'a t
 
+val singleton : 'a -> 'a t
+
+val of_list : 'a list -> 'a t
+
 val to_list : 'a t -> 'a list
-  (** Gather all values into a list *)
+(** Gather all values into a list *)
 
 type 'a sequence = ('a -> unit) -> unit
 type 'a gen = unit -> 'a option
@@ -44,7 +48,9 @@ val to_seq : 'a t -> 'a sequence
 val to_gen : 'a t -> 'a gen
 
 val fold : ('a -> 'b -> 'a) -> 'a -> 'b t -> 'a
-  (** Fold on values *)
+(** Fold on values *)
+
+val iter : ('a -> unit) -> 'a t -> unit
 
 val length : 'a t -> int
 
diff --git a/examples/mem_size.ml b/examples/mem_size.ml
index e89fb83c..d424e9ed 100644
--- a/examples/mem_size.ml
+++ b/examples/mem_size.ml
@@ -1,7 +1,7 @@
 (** Compute the memory footprint of a value (and its subvalues). Reference is
     http://rwmj.wordpress.com/2009/08/05/ocaml-internals-part-2-strings-and-other-types/ *)
 
-open Sequence.Infix
+module Sequence = CCSequence
 
 (** A graph vertex is an Obj.t value *)
 let graph =