printing functions

sequence.ml

@@ -713,3 +713,16 @@ let pp_seq ?(sep=", ") pp_elt formatter seq =
         end);
       pp_elt formatter x)
     seq
+
+let pp_buf ?(sep=", ") pp_elt buf seq =
+  let first = ref true in
+  iter
+    (fun x -> 
+      if !first then first := false else Buffer.add_string buf sep;
+      pp_elt buf x)
+    seq
+
+let to_string ?sep pp_elt seq =
+  let buf = Buffer.create 25 in
+  pp_buf ?sep (fun buf x -> Buffer.add_string buf (pp_elt x)) buf seq;
+  Buffer.contents buf

sequence.mli

@@ -442,3 +442,10 @@ val pp_seq : ?sep:string -> (Format.formatter -> 'a -> unit) ->
              Format.formatter -> 'a t -> unit
   (** Pretty print a sequence of ['a], using the given pretty printer
       to print each elements. An optional separator string can be provided. *)
+
+val pp_buf : ?sep:string -> (Buffer.t -> 'a -> unit) ->
+             Buffer.t -> 'a t -> unit
+  (** Print into a buffer *)
+
+val to_string : ?sep:string -> ('a -> string) -> 'a t -> string
+  (** Print into a string *)