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Standard Library

Below is the API for the OCaml standard library. It's directly copied over from the OCaml Manual, formatted to the Reason syntax and styled accordingly. The API docs are work-in-progress; we'll be polishing these gradually!

If you're targeting JavaScript, the API docs for BuckleScript includes all of below, plus JS-specific APIs.

Module BytesLabels

module BytesLabels: sig .. end
Byte sequence operations.
Since 4.02.0

let length: bytes => int;
Return the length (number of bytes) of the argument.
let get: bytes => int => char;
get s n returns the byte at index n in argument s.

Raise Invalid_argument if n not a valid index in s.

let set: bytes => int => char => unit;
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.

let create: int => bytes;
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.

let 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.

let 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.

Raise Invalid_argument if n < 0 or n > Sys.max_string_length.

let empty: bytes;
A byte sequence of size 0.
let copy: bytes => bytes;
Return a new byte sequence that contains the same bytes as the argument.
let of_string: string => bytes;
Return a new byte sequence that contains the same bytes as the given string.
let to_string: bytes => string;
Return a new string that contains the same bytes as the given byte sequence.
let 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.

Raise Invalid_argument if start and len do not designate a valid range of s.

let sub_string: bytes => int => int => string;
Same as sub but return a string instead of a byte sequence.
let 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.

Raise Invalid_argument if start and len do not designate a valid range of s.

let 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.

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.

let concat: sep::bytes => list bytes => 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.
let 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)); ().
let 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.
let 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.
let 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.
let 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'.
let escaped: bytes => bytes;
Return a copy of the argument, with special characters represented by escape sequences, following the lexical conventions of OCaml.
let 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.

let 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.

let 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.

let 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.

let contains: bytes => char => bool;
contains s c tests if byte c appears in s.
let 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.

let 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.

let 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.
let 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.
let capitalize: bytes => bytes;
Return a copy of the argument, with the first byte set to uppercase.
let 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.
let 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.