(**************************************************************************) (* *) (* OCaml *) (* *) (* Xavier Leroy, projet Cristal, INRIA Rocquencourt *) (* *) (* Copyright 1996 Institut National de Recherche en Informatique et *) (* en Automatique. *) (* *) (* All rights reserved. This file is distributed under the terms of *) (* the GNU Lesser General Public License version 2.1, with the *) (* special exception on linking described in the file LICENSE. *) (* *) (**************************************************************************) type 'a t = { mutable c : 'a list; mutable len : int; } exception Empty let create () = { c = []; len = 0; } let clear s = s.c <- []; s.len <- 0 let copy s = { c = s.c; len = s.len; } let push x s = s.c <- x :: s.c; s.len <- s.len + 1 let pop s = match s.c with | hd::tl -> s.c <- tl; s.len <- s.len - 1; hd | [] -> raise Empty let pop_opt s = match s.c with | hd::tl -> s.c <- tl; s.len <- s.len - 1; Some hd | [] -> None let top s = match s.c with | hd::_ -> hd | [] -> raise Empty let top_opt s = match s.c with | hd::_ -> Some hd | [] -> None let is_empty s = (s.c = []) let length s = s.len let iter f s = List.iter f s.c let fold f acc s = List.fold_left f acc s.c (** {1 Iterators} *) let to_seq s = List.to_seq s.c let add_seq q i = Seq.iter (fun x -> push x q) i let of_seq g = let s = create() in add_seq s g; s