module UnicodeString

: sig

Signature for Unicode strings. [root:UText], [root:XString], [root:UTF8], [root:UTF16], [root:UCS4] have matched signatures to UStorage and satisfy the semantics described below. If users want to supply their own Unicode strings, please design the module with the following signature and properties.

module type Type = sig

type t

The type of string.

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

get t i : i-th character of the storage.

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

init len f creates a new storage. the returned storage has length len, its nth-element is f n. f is called with integers 0 ... len - 1, only once for each integer. The call is in the increasing order f 0, f 1, f 2, ...

val length : t -> int

The number of Unicode characters in the storage

type index

locations in storages.

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

look t i : The character in the location i of t.

val nth : t -> int -> index

nth t n : the location of the n-th character in t.

next x i, prev x i : The operation is valid if i points the valid element, i.e. the returned value may point the location beyond valid elements by one. If i does not point a valid element, the results are unspecified.

val next : t -> index -> index

val prev : t -> index -> index

val out_of_range : t -> index -> bool

val iter : (UChar.t -> unit) -> t -> unit

val compare : t -> t -> int

val first : t -> index

The location of the first character in the storage.

val last : t -> index

The location of the last character in the storage.

val move : t -> index -> int -> index

move t i n : if n >= 0, then returns n-th character after i and otherwise returns -n-th character before i. If there is no such character, or i does not point a valid character, the result is unspecified.

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

compare_index t i j returns a positive integer if i is the location placed after j in t, 0 if i and j point the same location, and a negative integer if i is the location placed before j in t.

module Buf : sig

Character buffers. Similar to Buffer.

type buf

val create : int -> buf

create n creates the buffer. n is used to determine the initial size of the buffer. The meaning of n differs from modules to modules.

val contents : buf -> t

val clear : buf -> unit

val reset : buf -> unit

val add_char : buf -> UChar.t -> unit

val add_string : buf -> t -> unit

val add_buffer : buf -> buf -> unit

end