107 lines
3.5 KiB
OCaml
107 lines
3.5 KiB
OCaml
(***********************************************************************)
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(* *)
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(* Ocaml *)
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(* *)
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(* Daniel de Rauglaudre, projet Cristal, INRIA Rocquencourt *)
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(* *)
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(* Copyright 1997 Institut National de Recherche en Informatique et *)
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(* en Automatique. All rights reserved. This file is distributed *)
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(* under the terms of the GNU Library General Public License, with *)
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(* the special exception on linking described in file ../LICENSE. *)
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(* *)
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(***********************************************************************)
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(* $Id$ *)
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(** Streams and parsers. *)
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type 'a t
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(** The type of streams holding values of type ['a]. *)
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exception Failure
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(** Raised by parsers when none of the first components of the stream
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patterns is accepted. *)
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exception Error of string
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(** Raised by parsers when the first component of a stream pattern is
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accepted, but one of the following components is rejected. *)
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(** {2 Stream builders}
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Warning: these functions create streams with fast access; it is illegal
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to mix them with streams built with [[< >]]; would raise [Failure]
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when accessing such mixed streams.
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*)
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val from : (int -> 'a option) -> 'a t
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(** [Stream.from f] returns a stream built from the function [f].
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To create a new stream element, the function [f] is called with
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the current stream count. The user function [f] must return either
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[Some <value>] for a value or [None] to specify the end of the
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stream. *)
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val of_list : 'a list -> 'a t
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(** Return the stream holding the elements of the list in the same
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order. *)
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val of_string : string -> char t
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(** Return the stream of the characters of the string parameter. *)
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val of_channel : in_channel -> char t
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(** Return the stream of the characters read from the input channel. *)
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(** {2 Stream iterator} *)
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val iter : ('a -> unit) -> 'a t -> unit
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(** [Stream.iter f s] scans the whole stream s, applying function [f]
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in turn to each stream element encountered. *)
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(** {2 Predefined parsers} *)
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val next : 'a t -> 'a
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(** Return the first element of the stream and remove it from the
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stream. Raise Stream.Failure if the stream is empty. *)
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val empty : 'a t -> unit
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(** Return [()] if the stream is empty, else raise [Stream.Failure]. *)
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(** {2 Useful functions} *)
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val peek : 'a t -> 'a option
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(** Return [Some] of "the first element" of the stream, or [None] if
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the stream is empty. *)
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val junk : 'a t -> unit
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(** Remove the first element of the stream, possibly unfreezing
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it before. *)
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val count : 'a t -> int
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(** Return the current count of the stream elements, i.e. the number
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of the stream elements discarded. *)
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val npeek : int -> 'a t -> 'a list
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(** [npeek n] returns the list of the [n] first elements of
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the stream, or all its remaining elements if less than [n]
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elements are available. *)
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(**/**)
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(** {2 For system use only, not for the casual user} *)
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val iapp : 'a t -> 'a t -> 'a t
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val icons : 'a -> 'a t -> 'a t
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val ising : 'a -> 'a t
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val lapp : (unit -> 'a t) -> 'a t -> 'a t
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val lcons : (unit -> 'a) -> 'a t -> 'a t
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val lsing : (unit -> 'a) -> 'a t
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val sempty : 'a t
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val slazy : (unit -> 'a t) -> 'a t
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val dump : ('a -> unit) -> 'a t -> unit
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