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/OCaml

Module BytesLabels

module BytesLabels: sig .. end

Byte sequence operations.

  • Since 4.02.0 This module is intended to be used through {!StdLabels} which replaces {!Array}, {!Bytes}, {!List} and {!String} with their labeled counterparts. For example: {[ open StdLabels let first = Bytes.sub ~pos:0 ~len:1 ]}

val length : bytes -> int

Return the length (number of bytes) of the argument.

val get : bytes -> int -> char

get s n returns the byte at index n in argument s.

  • Raises Invalid_argument if n is not a valid index in s.
val set : bytes -> int -> char -> unit

set s n c modifies s in place, replacing the byte at index n with c.

  • Raises Invalid_argument if n is not a valid index in s.
val create : int -> bytes

create n returns a new byte sequence of length n. The sequence is uninitialized and contains arbitrary bytes.

val make : int -> char -> bytes

make n c returns a new byte sequence of length n, filled with the byte c.

val init : int -> f:(int -> char) -> bytes

init n f returns a fresh byte sequence of length n, with character i initialized to the result of f i.

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 -> pos:int -> len: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.

  • Raises Invalid_argument if start and len do not designate a valid range of s.
val sub_string : bytes -> pos:int -> len:int -> string

Same as sub but return a string instead of a byte sequence.

val extend : bytes -> left:int -> right:int -> bytes

extend s left right returns a new byte sequence that contains the bytes of s, with left uninitialized bytes prepended and right uninitialized bytes appended to it. If left or right is negative, then bytes are removed (instead of appended) from the corresponding side of s.

  • Since 4.05.0
  • Raises Invalid_argument if the result length is negative or longer than Sys.max_string_length bytes.
val fill : bytes -> pos:int -> len:int -> char -> unit

fill s start len c modifies s in place, replacing len characters with c, starting at start.

  • Raises Invalid_argument if start and len do not designate a valid range of s.
val blit : src:bytes -> src_pos:int -> dst:bytes -> dst_pos:int -> len: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.

  • Raises 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 blit_string : src:string -> src_pos:int -> dst:bytes -> dst_pos:int -> len:int -> unit

blit src srcoff dst dstoff len copies len bytes from string src, starting at index srcoff, to byte sequence dst, starting at index dstoff.

  • Since 4.05.0
  • Raises 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 : sep: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 cat : bytes -> bytes -> bytes

cat s1 s2 concatenates s1 and s2 and returns the result as new byte sequence.

val iter : f:(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 : f:(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 : f:(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 mapi : f:(int -> char -> char) -> bytes -> bytes

mapi f s calls f with each character of s and its index (in increasing index order) 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.

  • Raises Not_found if c does not occur in s.
val index_opt : bytes -> char -> int option

index_opt s c returns the index of the first occurrence of byte c in s or None if c does not occur in s.

  • Since 4.05
val rindex : bytes -> char -> int

rindex s c returns the index of the last occurrence of byte c in s.

  • Raises Not_found if c does not occur in s.
val rindex_opt : bytes -> char -> int option

rindex_opt s c returns the index of the last occurrence of byte c in s or None if c does not occur in s.

  • Since 4.05
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.

  • Raises
    • Invalid_argument if i is not a valid position in s.
    • Not_found if c does not occur in s after position i.
val index_from_opt : bytes -> int -> char -> int option

index_from _opts i c returns the index of the first occurrence of byte c in s after position i or None if c does not occur in s after position i. Bytes.index_opt s c is equivalent to Bytes.index_from_opt s 0 c.

  • Since 4.05
  • Raises Invalid_argument if i is not a valid position in s.
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.

  • Raises
    • Invalid_argument if i+1 is not a valid position in s.
    • Not_found if c does not occur in s before position i+1.
val rindex_from_opt : bytes -> int -> char -> int option

rindex_from_opt s i c returns the index of the last occurrence of byte c in s before position i+1 or None if c does not occur in s before position i+1. rindex_opt s c is equivalent to rindex_from s (Bytes.length s - 1) c.

  • Since 4.05
  • Raises Invalid_argument if i+1 is not a valid position in s.
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
.

  • Raises 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.

  • Raises Invalid_argument if stop < 0 or stop+1 is not a valid position in s.
val uppercase : bytes -> bytes
Deprecated.Functions operating on Latin-1 character set are deprecated.

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
Deprecated.Functions operating on Latin-1 character set are deprecated.

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
Deprecated.Functions operating on Latin-1 character set are deprecated.

Return a copy of the argument, with the first character set to uppercase, using the ISO Latin-1 (8859-1) character set..

val uncapitalize : bytes -> bytes
Deprecated.Functions operating on Latin-1 character set are deprecated.

Return a copy of the argument, with the first character set to lowercase, using the ISO Latin-1 (8859-1) character set..

val uppercase_ascii : bytes -> bytes

Return a copy of the argument, with all lowercase letters translated to uppercase, using the US-ASCII character set.

  • Since 4.05.0
val lowercase_ascii : bytes -> bytes

Return a copy of the argument, with all uppercase letters translated to lowercase, using the US-ASCII character set.

  • Since 4.05.0
val capitalize_ascii : bytes -> bytes

Return a copy of the argument, with the first character set to uppercase, using the US-ASCII character set.

  • Since 4.05.0
val uncapitalize_ascii : bytes -> bytes

Return a copy of the argument, with the first character set to lowercase, using the US-ASCII character set.

  • Since 4.05.0
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 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.

val equal : t -> t -> bool

The equality function for byte sequences.

  • Since 4.05.0

Iterators

val to_seq : t -> char Seq.t

Iterate on the string, in increasing index order. Modifications of the string during iteration will be reflected in the iterator.

  • Since 4.07
val to_seqi : t -> (int * char) Seq.t

Iterate on the string, in increasing order, yielding indices along chars

  • Since 4.07
val of_seq : char Seq.t -> t

Create a string from the generator

  • Since 4.07

Binary encoding/decoding of integers

The functions in this section binary encode and decode integers to and from byte sequences.

All following functions raise Invalid_argument if the space needed at index i to decode or encode the integer is not available.

Little-endian (resp. big-endian) encoding means that least (resp. most) significant bytes are stored first. Big-endian is also known as network byte order. Native-endian encoding is either little-endian or big-endian depending on Sys.big_endian.

32-bit and 64-bit integers are represented by the int32 and int64 types, which can be interpreted either as signed or unsigned numbers.

8-bit and 16-bit integers are represented by the int type, which has more bits than the binary encoding. These extra bits are handled as follows:

  • Functions that decode signed (resp. unsigned) 8-bit or 16-bit integers represented by int values sign-extend (resp. zero-extend) their result.
  • Functions that encode 8-bit or 16-bit integers represented by int values truncate their input to their least significant bytes.
val get_uint8 : bytes -> int -> int

get_uint8 b i is b's unsigned 8-bit integer starting at byte index i.

  • Since 4.08
val get_int8 : bytes -> int -> int

get_int8 b i is b's signed 8-bit integer starting at byte index i.

  • Since 4.08
val get_uint16_ne : bytes -> int -> int

get_uint16_ne b i is b's native-endian unsigned 16-bit integer starting at byte index i.

  • Since 4.08
val get_uint16_be : bytes -> int -> int

get_uint16_be b i is b's big-endian unsigned 16-bit integer starting at byte index i.

  • Since 4.08
val get_uint16_le : bytes -> int -> int

get_uint16_le b i is b's little-endian unsigned 16-bit integer starting at byte index i.

  • Since 4.08
val get_int16_ne : bytes -> int -> int

get_int16_ne b i is b's native-endian signed 16-bit integer starting at byte index i.

  • Since 4.08
val get_int16_be : bytes -> int -> int

get_int16_be b i is b's big-endian signed 16-bit integer starting at byte index i.

  • Since 4.08
val get_int16_le : bytes -> int -> int

get_int16_le b i is b's little-endian signed 16-bit integer starting at byte index i.

  • Since 4.08
val get_int32_ne : bytes -> int -> int32

get_int32_ne b i is b's native-endian 32-bit integer starting at byte index i.

  • Since 4.08
val get_int32_be : bytes -> int -> int32

get_int32_be b i is b's big-endian 32-bit integer starting at byte index i.

  • Since 4.08
val get_int32_le : bytes -> int -> int32

get_int32_le b i is b's little-endian 32-bit integer starting at byte index i.

  • Since 4.08
val get_int64_ne : bytes -> int -> int64

get_int64_ne b i is b's native-endian 64-bit integer starting at byte index i.

  • Since 4.08
val get_int64_be : bytes -> int -> int64

get_int64_be b i is b's big-endian 64-bit integer starting at byte index i.

  • Since 4.08
val get_int64_le : bytes -> int -> int64

get_int64_le b i is b's little-endian 64-bit integer starting at byte index i.

  • Since 4.08
val set_uint8 : bytes -> int -> int -> unit

set_uint8 b i v sets b's unsigned 8-bit integer starting at byte index i to v.

  • Since 4.08
val set_int8 : bytes -> int -> int -> unit

set_int8 b i v sets b's signed 8-bit integer starting at byte index i to v.

  • Since 4.08
val set_uint16_ne : bytes -> int -> int -> unit

set_uint16_ne b i v sets b's native-endian unsigned 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_uint16_be : bytes -> int -> int -> unit

set_uint16_be b i v sets b's big-endian unsigned 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_uint16_le : bytes -> int -> int -> unit

set_uint16_le b i v sets b's little-endian unsigned 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_int16_ne : bytes -> int -> int -> unit

set_int16_ne b i v sets b's native-endian signed 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_int16_be : bytes -> int -> int -> unit

set_int16_be b i v sets b's big-endian signed 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_int16_le : bytes -> int -> int -> unit

set_int16_le b i v sets b's little-endian signed 16-bit integer starting at byte index i to v.

  • Since 4.08
val set_int32_ne : bytes -> int -> int32 -> unit

set_int32_ne b i v sets b's native-endian 32-bit integer starting at byte index i to v.

  • Since 4.08
val set_int32_be : bytes -> int -> int32 -> unit

set_int32_be b i v sets b's big-endian 32-bit integer starting at byte index i to v.

  • Since 4.08
val set_int32_le : bytes -> int -> int32 -> unit

set_int32_le b i v sets b's little-endian 32-bit integer starting at byte index i to v.

  • Since 4.08
val set_int64_ne : bytes -> int -> int64 -> unit

set_int64_ne b i v sets b's native-endian 64-bit integer starting at byte index i to v.

  • Since 4.08
val set_int64_be : bytes -> int -> int64 -> unit

set_int64_be b i v sets b's big-endian 64-bit integer starting at byte index i to v.

  • Since 4.08
val set_int64_le : bytes -> int -> int64 -> unit

set_int64_le b i v sets b's little-endian 64-bit integer starting at byte index i to v.

  • Since 4.08