stringCodepointSplitter/stringCodepointSplitter.ml
2023-08-27 01:46:01 +08:00

54 lines
1.6 KiB
OCaml

(*#use "topfind";;*)
open Stdlib
open Uutf
(**
The Module needs [Uutf] Module.
It only contains [split_string_by_unicode_codepoint], which splits an OCaml string [str] to a [string list]
*)
(** Split an OCaml string [str] to a [string list]
{b Arguments}
{ul
{- [str] the string to be splitted.
}}
{b Example}
{[let example= split_string_by_unicode_codepoint "m̄知 who you're." (*don't know who you are*) in
List.map (fun x -> print_string (x ^ ", ")) (split_string_by_unicode_codepoint example);;
(*it will output : "m, ̄, 知, , w, h, o, , y, o, u, ', r, e, ., "*)]}
*)
let split_string_by_unicode_codepoint str =
(*Split a Ocaml string [str] to a `str list` *)
let pred_codepoint = ref (-1) in
let segmented_unit_list = ref [] in
let iterator x y z =
let _ = if !pred_codepoint > -1 then
let current_codepoint = y in
let pred_char_len = current_codepoint - !pred_codepoint in
let unit_substring = Stdlib.String.sub x !pred_codepoint pred_char_len in
let _ = segmented_unit_list := !segmented_unit_list @ [unit_substring] in
unit_substring
else
"" in
let _ = pred_codepoint := y in x in
let _ = Uutf.String.fold_utf_8 iterator str str in
let last_char_len = (Stdlib.String.length str) - !pred_codepoint in
if last_char_len > 0 then
let unit_substring = Stdlib.String.sub str !pred_codepoint last_char_len in
let _ = segmented_unit_list := !segmented_unit_list @ [unit_substring] in
!segmented_unit_list
else
!segmented_unit_list;;
List.map (fun x -> print_string (x ^ ", ")) (split_string_by_unicode_codepoint "m̄知 who you're.");;