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module S = Stdlib.String
include S
let to_list : string -> char list =
fun s ->
let l = ref [] in
S.iter (fun c -> l := c :: !l) s;
List.rev !l
let of_list : char list -> string =
fun l ->
let b = Buffer.create 37 in
List.iter (Buffer.add_char b) l;
Buffer.contents b
let is_substring : string -> string -> bool =
fun e s ->
let len_e = S.length e in
let len_s = S.length s in
let rec is_sub i =
if len_s - i < len_e then false
else if S.sub s i len_e = e then true
else is_sub (i + 1)
in
is_sub 0
let is_prefix : string -> string -> bool =
fun p s ->
let len_p = S.length p in
let len_s = S.length s in
len_p <= len_s && S.sub s 0 len_p = p
let for_all : (char -> bool) -> string -> bool =
fun p s ->
let len_s = S.length s in
let rec for_all i = i >= len_s || (p (S.get s i) && for_all (i + 1)) in
for_all 0