Sha256: fb66522626e5016f226d3741264ed4a3f28100b6c8f25f5d3e23f98426c485d9
Contents?: true
Size: 509 Bytes
Versions: 44
Compression:
Stored size: 509 Bytes
Contents
open Base
let every_second_digit_doubled =
let double_digit n = let d = n * 2 in if d >= 10 then d - 9 else d in
List.rev_mapi ~f:(fun i -> if i % 2 = 1 then double_digit else Fn.id)
let valid s =
let s = String.filter s ~f:(fun ch -> Char.(ch <> ' ')) in
if String.length s > 1
then
let checksum = String.to_list s
|> List.rev_map ~f:(fun ch -> Char.to_int ch - Char.to_int '0')
|> every_second_digit_doubled
|> List.sum (module Int) ~f:Fn.id in
checksum % 10 = 0
else false
Version data entries
44 entries across 44 versions & 1 rubygems