227 lines
8.8 KiB
OCaml
227 lines
8.8 KiB
OCaml
|
(***********************************************************************)
|
||
|
|
(* *)
|
||
|
|
(* 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 Library General Public License, with *)
|
||
|
|
(* the special exception on linking described in file ../LICENSE. *)
|
||
|
|
(* *)
|
||
|
|
(***********************************************************************)
|
||
|
|
|
||
|
|
(** Byte sequence operations.
|
||
|
|
|
||
|
|
A byte sequence is a mutable data structure that contains a
|
||
|
|
fixed-length sequence of bytes. Each byte can be indexed in
|
||
|
|
constant time for reading or writing.
|
||
|
|
|
||
|
|
Given a byte sequence [s] of length [l], we can access each of the
|
||
|
|
[l] bytes of [s] via its index in the sequence. Indexes start at
|
||
|
|
[0], and we will call an index valid in [s] if it falls within the
|
||
|
|
range [[0...l-1]] (inclusive). A position is the point between two
|
||
|
|
bytes or at the beginning or end of the sequence. We call a
|
||
|
|
position valid in [s] if it falls within the range [[0...l]]
|
||
|
|
(inclusive). Note that the byte at index [n] is between positions
|
||
|
|
[n] and [n+1].
|
||
|
|
|
||
|
|
Two parameters [start] and [len] are said to designate a valid
|
||
|
|
range of [s] if [len >= 0] and [start] and [start+len] are valid
|
||
|
|
positions in [s].
|
||
|
|
|
||
|
|
Byte sequences can be modified in place, for instance via the [set]
|
||
|
|
and [blit] functions described below. See also strings (module
|
||
|
|
{!String}), which are almost the same data structure, but cannot be
|
||
|
|
modified in place.
|
||
|
|
|
||
|
|
Bytes are represented by the OCaml type [char].
|
||
|
|
|
||
|
|
@since 4.02.0
|
||
|
|
*)
|
||
|
|
|
||
|
|
external length : bytes -> int = "%string_length"
|
||
|
|
(** Return the length (number of bytes) of the argument. *)
|
||
|
|
|
||
|
|
external get : bytes -> int -> char = "%string_safe_get"
|
||
|
|
(** [get s n] returns the byte at index [n] in argument [s].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [n] not a valid index in [s]. *)
|
||
|
|
|
||
|
|
external set : bytes -> int -> char -> unit = "%string_safe_set"
|
||
|
|
(** [set s n c] modifies [s] in place, replacing the byte at index [n]
|
||
|
|
with [c].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [n] is not a valid index in [s]. *)
|
||
|
|
|
||
|
|
external create : int -> bytes = "caml_create_string"
|
||
|
|
(** [create n] returns a new byte sequence of length [n]. The
|
||
|
|
sequence is uninitialized and contains arbitrary bytes.
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [n < 0] or [n > ]{!Sys.max_string_length}. *)
|
||
|
|
|
||
|
|
val make : int -> char -> bytes
|
||
|
|
(** [make n c] returns a new byte sequence of length [n], filled with
|
||
|
|
the byte [c].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [n < 0] or [n > ]{!Sys.max_string_length}. *)
|
||
|
|
|
||
|
|
val empty : bytes
|
||
|
|
(** A byte sequence of size 0. *)
|
||
|
|
|
||
|
|
val copy : bytes -> bytes
|
||
|
|
(** Return a new byte sequence that contains the same bytes as the
|
||
|
|
argument. *)
|
||
|
|
|
||
|
|
val of_string : string -> bytes
|
||
|
|
(** Return a new byte sequence that contains the same bytes as the
|
||
|
|
given string. *)
|
||
|
|
|
||
|
|
val to_string : bytes -> string
|
||
|
|
(** Return a new string that contains the same bytes as the given byte
|
||
|
|
sequence. *)
|
||
|
|
|
||
|
|
val sub : bytes -> int -> int -> bytes
|
||
|
|
(** [sub s start len] returns a new byte sequence of length [len],
|
||
|
|
containing the subsequence of [s] that starts at position [start]
|
||
|
|
and has length [len].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [start] and [len] do not designate a
|
||
|
|
valid range of [s]. *)
|
||
|
|
|
||
|
|
val sub_string : bytes -> int -> int -> string
|
||
|
|
(** Same as [sub] but return a string instead of a byte sequence. *)
|
||
|
|
|
||
|
|
val fill : bytes -> int -> int -> char -> unit
|
||
|
|
(** [fill s start len c] modifies [s] in place, replacing [len]
|
||
|
|
characters with [c], starting at [start].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [start] and [len] do not designate a
|
||
|
|
valid range of [s]. *)
|
||
|
|
|
||
|
|
val blit : bytes -> int -> bytes -> int -> int -> unit
|
||
|
|
(** [blit src srcoff dst dstoff len] copies [len] bytes from sequence
|
||
|
|
[src], starting at index [srcoff], to sequence [dst], starting at
|
||
|
|
index [dstoff]. It works correctly even if [src] and [dst] are the
|
||
|
|
same byte sequence, and the source and destination intervals
|
||
|
|
overlap.
|
||
|
|
|
||
|
|
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]. *)
|
||
|
|
|
||
|
|
val concat : bytes -> bytes list -> bytes
|
||
|
|
(** [concat sep sl] concatenates the list of byte sequences [sl],
|
||
|
|
inserting the separator byte sequence [sep] between each, and
|
||
|
|
returns the result as a new byte sequence. *)
|
||
|
|
|
||
|
|
val iter : (char -> unit) -> bytes -> unit
|
||
|
|
(** [iter f s] applies function [f] in turn to all the bytes of [s].
|
||
|
|
It is equivalent to [f (get s 0); f (get s 1); ...; f (get s
|
||
|
|
(length s - 1)); ()]. *)
|
||
|
|
|
||
|
|
val iteri : (int -> char -> unit) -> bytes -> unit
|
||
|
|
(** Same as {!Bytes.iter}, but the function is applied to the index of
|
||
|
|
the byte as first argument and the byte itself as second
|
||
|
|
argument. *)
|
||
|
|
|
||
|
|
val map : (char -> char) -> bytes -> bytes
|
||
|
|
(** [map f s] applies function [f] in turn to all the bytes of [s] and
|
||
|
|
stores the resulting bytes in a new sequence that is returned as
|
||
|
|
the result. *)
|
||
|
|
|
||
|
|
val trim : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, without leading and trailing
|
||
|
|
whitespace. The bytes regarded as whitespace are the ASCII
|
||
|
|
characters [' '], ['\012'], ['\n'], ['\r'], and ['\t']. *)
|
||
|
|
|
||
|
|
val escaped : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, with special characters represented
|
||
|
|
by escape sequences, following the lexical conventions of OCaml. *)
|
||
|
|
|
||
|
|
val index : bytes -> char -> int
|
||
|
|
(** [index s c] returns the index of the first occurrence of byte [c]
|
||
|
|
in [s].
|
||
|
|
|
||
|
|
Raise [Not_found] if [c] does not occur in [s]. *)
|
||
|
|
|
||
|
|
val rindex : bytes -> char -> int
|
||
|
|
(** [rindex s c] returns the index of the last occurrence of byte [c]
|
||
|
|
in [s].
|
||
|
|
|
||
|
|
Raise [Not_found] if [c] does not occur in [s]. *)
|
||
|
|
|
||
|
|
val index_from : bytes -> int -> char -> int
|
||
|
|
(** [index_from s i c] returns the index of the first occurrence of
|
||
|
|
byte [c] in [s] after position [i]. [Bytes.index s c] is
|
||
|
|
equivalent to [Bytes.index_from s 0 c].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [i] is not a valid position in [s].
|
||
|
|
Raise [Not_found] if [c] does not occur in [s] after position [i]. *)
|
||
|
|
|
||
|
|
val rindex_from : bytes -> int -> char -> int
|
||
|
|
(** [rindex_from s i c] returns the index of the last occurrence of
|
||
|
|
byte [c] in [s] before position [i+1]. [rindex s c] is equivalent
|
||
|
|
to [rindex_from s (Bytes.length s - 1) c].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [i+1] is not a valid position in [s].
|
||
|
|
Raise [Not_found] if [c] does not occur in [s] before position [i+1]. *)
|
||
|
|
|
||
|
|
val contains : bytes -> char -> bool
|
||
|
|
(** [contains s c] tests if byte [c] appears in [s]. *)
|
||
|
|
|
||
|
|
val contains_from : bytes -> int -> char -> bool
|
||
|
|
(** [contains_from s start c] tests if byte [c] appears in [s] after
|
||
|
|
position [start]. [contains s c] is equivalent to [contains_from
|
||
|
|
s 0 c].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [start] is not a valid position in [s]. *)
|
||
|
|
|
||
|
|
val rcontains_from : bytes -> int -> char -> bool
|
||
|
|
(** [rcontains_from s stop c] tests if byte [c] appears in [s] before
|
||
|
|
position [stop+1].
|
||
|
|
|
||
|
|
Raise [Invalid_argument] if [stop < 0] or [stop+1] is not a valid
|
||
|
|
position in [s]. *)
|
||
|
|
|
||
|
|
val uppercase : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, with all lowercase letters
|
||
|
|
translated to uppercase, including accented letters of the ISO
|
||
|
|
Latin-1 (8859-1) character set. *)
|
||
|
|
|
||
|
|
val lowercase : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, with all uppercase letters
|
||
|
|
translated to lowercase, including accented letters of the ISO
|
||
|
|
Latin-1 (8859-1) character set. *)
|
||
|
|
|
||
|
|
val capitalize : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, with the first byte set to
|
||
|
|
uppercase. *)
|
||
|
|
|
||
|
|
val uncapitalize : bytes -> bytes
|
||
|
|
(** Return a copy of the argument, with the first byte set to
|
||
|
|
lowercase. *)
|
||
|
|
|
||
|
|
type t = bytes
|
||
|
|
(** An alias for the type of byte sequences. *)
|
||
|
|
|
||
|
|
val compare: t -> t -> int
|
||
|
|
(** The comparison function for byte sequences, with the same
|
||
|
|
specification as {!Pervasives.compare}. Along with the type [t],
|
||
|
|
this function [compare] allows the module [Bytes] to be passed as
|
||
|
|
argument to the functors {!Set.Make} and {!Map.Make}. *)
|
||
|
|
|
||
|
|
(**/**)
|
||
|
|
|
||
|
|
(* The following is for system use only. Do not call directly. *)
|
||
|
|
|
||
|
|
external unsafe_get : bytes -> int -> char = "%string_unsafe_get"
|
||
|
|
external unsafe_set : bytes -> int -> char -> unit = "%string_unsafe_set"
|
||
|
|
external unsafe_blit :
|
||
|
|
bytes -> int -> bytes -> int -> int -> unit
|
||
|
|
= "caml_blit_string" "noalloc"
|
||
|
|
external unsafe_fill :
|
||
|
|
bytes -> int -> int -> char -> unit = "caml_fill_string" "noalloc"
|
||
|
|
external unsafe_to_string : bytes -> string = "%identity"
|
||
|
|
external unsafe_of_string : string -> bytes = "%identity"
|