Sha256: 85e7a8ae6f347446def1d11a63c92e208b28b46fd4520a8560be3935001bb654
Contents?: true
Size: 794 Bytes
Versions: 50
Compression:
Stored size: 794 Bytes
Contents
module PhoneNumber
( phoneNumber
)
where
import Prelude ((==), (<), (>>=), (&&), ($), otherwise)
import Data.Char.Unicode (isDigit)
import Data.Array (filter, head, tail, length, (!!))
import Data.String (toCharArray, fromCharArray)
import Data.Maybe (Maybe(..), fromMaybe)
clean :: String -> Maybe (Array Char)
clean input = go where
go
| len == 10 = Just digits
| len == 11 && head digits == Just '1' = tail digits
| otherwise = Nothing
digits = filter isDigit $ toCharArray input
len = length digits
check:: Array Char -> Maybe String
check input
| input !! 0 < Just '2' = Nothing
| input !! 3 < Just '2' = Nothing
| otherwise = Just $ fromCharArray input
phoneNumber :: String -> String
phoneNumber input = fromMaybe "None" (clean input >>= check)
Version data entries
50 entries across 50 versions & 1 rubygems