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|
(**************************************************************************)
(* *)
(* OCaml *)
(* *)
(* Daniel de Rauglaudre, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1997 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. *)
(* *)
(**************************************************************************)
(** Streams and parsers. *)
type ('e,'a) t
(** The type of streams holding values of type ['a].
Producing a new value needs an environment ['e]. *)
exception Failure
(** Raised by streams when trying to access beyond their end. *)
(** {1 Stream builders} *)
val from : ?offset:int -> ('e -> 'a option) -> ('e,'a) t
(** [Stream.from f] returns a stream built from the function [f]. To
create a new stream element, the function [f] is called. The user
function [f] must return either [Some <value>] for a value or
[None] to specify the end of the stream. [offset] will initialize
the stream [count] to start with [offset] consumed items, which is
useful for some uses cases such as parsing resumption.
*)
val empty : unit -> ('e,'a) t
(** Return the stream holding the elements of the list in the same
order. *)
val of_string : ?offset:int -> string -> (unit,char) t
(** Return the stream of the characters of the string parameter. If
set. [offset] parameter is similar to [from]. *)
val of_channel : in_channel -> (unit,char) t
(** Return the stream of the characters read from the input channel. *)
(** {1 Predefined parsers} *)
val next : 'e -> ('e,'a) t -> 'a
(** Return the first element of the stream and remove it from the
stream.
@raise Stream.Failure if the stream is empty. *)
val is_empty : 'e -> ('e,'a) t -> bool
(** Return [true] if the stream is empty, else [false]. *)
(** {1 Useful functions} *)
val peek : 'e -> ('e,'a) t -> 'a option
(** Return [Some] of "the first element" of the stream, or [None] if
the stream is empty. *)
val junk : 'e -> ('e,'a) t -> unit
(** Remove the first element of the stream, possibly unfreezing
it before. *)
val count : ('e,'a) t -> int
(** Return the current count of the stream elements, i.e. the number
of the stream elements discarded. *)
val npeek : 'e -> int -> ('e,'a) t -> 'a list
(** [npeek e n] returns the list of the [n] first elements of
the stream, or all its remaining elements if less than [n]
elements are available. *)
val nth : 'e -> int -> ('e,'a) t -> 'a
val njunk : 'e -> int -> ('e,'a) t -> unit
(**/**)
|
