WordNumber.hs

module WordNumber where

import Data.List (intersperse)

digitToWord :: Int -> String
digitToWord 0 = "Zero"
digitToWord 1 = "One"
digitToWord 2 = "Two"
digitToWord 3 = "Three"
digitToWord _ = "other"

digits :: Int -> [Int]
digits 0 = []
digits n = modVal : digits divVal
           where divVal  = (n `div` 10)
                 modVal  = (n `mod` 10)

wordNumber :: Int -> String
wordNumber n = concat . intersperse "-" . map digitToWord . reverse $ digits n