[Ocaml-lib-devel] String.unsafe_get not exported; String.for_all and String.exists

[Richard J. <ri...@an...>]

First of all a bug:  unsafe_get isn't exported by ExtString.String.

Here are a couple of functions for ExtString.String:

let for_all f str =
  let len = length str in
  let rec loop i =
    if i = len then true
    else (
      let c = unsafe_get str i in
      if not (f c) then false
      else loop (i+1)
    )
  in
  loop 0

let exists f str =
  let len = length str in
  let rec loop i =
    if i = len then false
    else (
      let c = unsafe_get str i in
      if f c then true
      else loop (i+1)
    )
  in
  loop 0

In particular, this lets you write:

let string_is_whitespace = String.for_all isspace

[Assuming you're using an ASCII-compatible encoding and you've defined
a suitable isspace function - see earlier discussion about that.]

Rich.

-- 
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