Module CamomileLib.UTF16

UTF-16 encoded string. the type is the bigarray of 16-bit integers. The characters must be 21-bits code points, and not surrogate points, 0xfffe, 0xffff. Bigarray.cma or Bigarray.cmxa must be linked when this module is used.

exception Malformed_code
val validate : t -> unit

validate s If s is valid UTF-16 then successes otherwise raises Malformed_code. Other functions assume strings are valid UTF-16, so it is prudent to test their validity for strings from untrusted origins.

All functions below assume strings are valid UTF-16. If not, the result is unspecified.

val get : t -> int -> UChar.t

get s n returns n-th Unicode character of s. The call requires O(n)-time.

exception Out_of_range
val init : int -> (int -> UChar.t) -> t

init len f returns a new string which contains len Unicode characters. The i-th Unicode character is initialized by f i if the character is not representable, raise Out_of_range.

val length : t -> int

length s returns the number of Unicode characters contained in s

type index = int

Positions in the string represented by the number of 16-bit unit from the head. The location of the first character is 0

val nth : t -> int -> index

nth s n returns the position of the n-th Unicode character. The call requires O(n)-time

val first : t -> index

first s : The position of the head of the last Unicode character.

val last : t -> index

last s : The position of the head of the last Unicode character.

val look : t -> index -> UChar.t

look s i returns the Unicode character of the location i in the string s.

val out_of_range : t -> index -> bool

out_of_range s i tests whether i is inside of s.

val compare_index : t -> index -> index -> int

compare_aux s i1 i2 returns

  • If i1 is the position located before i2, a value < 0,
  • If i1 and i2 points the same location, 0,
  • If i1 is the position located after i2, a value > 0.
val next : t -> index -> index

next s i returns the position of the head of the Unicode character located immediately after i.

  • If i is a valid position, the function always success.
  • If i is a valid position and there is no Unicode character after i, the position outside s is returned.
  • If i is not a valid position, the behaviour is undefined.
val prev : t -> index -> index

prev s i returns the position of the head of the Unicode character located immediately before i.

  • If i is a valid position, the function always success.
  • If i is a valid position and there is no Unicode character before i, the position outside s is returned.
  • If i is not a valid position, the behaviour is undefined.
val move : t -> index -> int -> index
val iter : (UChar.t -> unit) -> t -> unit

iter f s Apply f to all Unicode characters in s. The order of application is same to the order in the Unicode characters in s.

val compare : t -> t -> int

Code point comparison

module Buf : sig ... end

Buffer module for UTF-16