ligo/lib_protocol_environment_sigs/v1/buffer.mli

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(*                                                                        *)
(*                                 OCaml                                  *)
(*                                                                        *)
(*   Pierre Weis and Xavier Leroy, projet Cristal, INRIA Rocquencourt     *)
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(*   Copyright 1999 Institut National de Recherche en Informatique et     *)
(*     en Automatique.                                                    *)
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(*   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.          *)
(*                                                                        *)
(**************************************************************************)

(* TEZOS CHANGES

   * Import version 4.04.0
   * Remove channel functions

*)

(** Extensible buffers.

    This module implements buffers that automatically expand
    as necessary.  It provides accumulative concatenation of strings
    in quasi-linear time (instead of quadratic time when strings are
    concatenated pairwise).
*)

type t
(** The abstract type of buffers. *)

val create : int -> t
(** [create n] returns a fresh buffer, initially empty.
    The [n] parameter is the initial size of the internal byte sequence
    that holds the buffer contents. That byte sequence is automatically
    reallocated when more than [n] characters are stored in the buffer,
    but shrinks back to [n] characters when [reset] is called.
    For best performance, [n] should be of the same order of magnitude
    as the number of characters that are expected to be stored in
    the buffer (for instance, 80 for a buffer that holds one output
    line).  Nothing bad will happen if the buffer grows beyond that
    limit, however. In doubt, take [n = 16] for instance.
    If [n] is not between 1 and {!Sys.max_string_length}, it will
    be clipped to that interval. *)

val contents : t -> string
(** Return a copy of the current contents of the buffer.
    The buffer itself is unchanged. *)

val to_bytes : t -> bytes
(** Return a copy of the current contents of the buffer.
    The buffer itself is unchanged.
    @since 4.02 *)

val sub : t -> int -> int -> string
(** [Buffer.sub b off len] returns a copy of [len] bytes from the
    current contents of the buffer [b], starting at offset [off].

    Raise [Invalid_argument] if [srcoff] and [len] do not designate a valid
    range of [b]. *)

val blit : t -> int -> bytes -> int -> int -> unit
(** [Buffer.blit src srcoff dst dstoff len] copies [len] characters from
    the current contents of the buffer [src], starting at offset [srcoff]
    to [dst], starting at character [dstoff].

    Raise [Invalid_argument] if [srcoff] and [len] do not designate a valid
    range of [src], or if [dstoff] and [len] do not designate a valid
    range of [dst].
    @since 3.11.2
*)

val nth : t -> int -> char
(** Get the n-th character of the buffer. Raise [Invalid_argument] if
    index out of bounds *)

val length : t -> int
(** Return the number of characters currently contained in the buffer. *)

val clear : t -> unit
(** Empty the buffer. *)

val reset : t -> unit
(** Empty the buffer and deallocate the internal byte sequence holding the
    buffer contents, replacing it with the initial internal byte sequence
    of length [n] that was allocated by {!Buffer.create} [n].
    For long-lived buffers that may have grown a lot, [reset] allows
    faster reclamation of the space used by the buffer. *)

val add_char : t -> char -> unit
(** [add_char b c] appends the character [c] at the end of buffer [b]. *)

val add_string : t -> string -> unit
(** [add_string b s] appends the string [s] at the end of buffer [b]. *)

val add_bytes : t -> bytes -> unit
(** [add_bytes b s] appends the byte sequence [s] at the end of buffer [b].
    @since 4.02 *)

val add_substring : t -> string -> int -> int -> unit
(** [add_substring b s ofs len] takes [len] characters from offset
    [ofs] in string [s] and appends them at the end of buffer [b]. *)

val add_subbytes : t -> bytes -> int -> int -> unit
(** [add_subbytes b s ofs len] takes [len] characters from offset
    [ofs] in byte sequence [s] and appends them at the end of buffer [b].
    @since 4.02 *)

val add_substitute : t -> (string -> string) -> string -> unit
(** [add_substitute b f s] appends the string pattern [s] at the end
    of buffer [b] with substitution.
    The substitution process looks for variables into
    the pattern and substitutes each variable name by its value, as
    obtained by applying the mapping [f] to the variable name. Inside the
    string pattern, a variable name immediately follows a non-escaped
    [$] character and is one of the following:
    - a non empty sequence of alphanumeric or [_] characters,
    - an arbitrary sequence of characters enclosed by a pair of
    matching parentheses or curly brackets.
    An escaped [$] character is a [$] that immediately follows a backslash
    character; it then stands for a plain [$].
    Raise [Not_found] if the closing character of a parenthesized variable
    cannot be found. *)

val add_buffer : t -> t -> unit
(** [add_buffer b1 b2] appends the current contents of buffer [b2]
    at the end of buffer [b1].  [b2] is not modified. *)