{- binmain.hs -}

import Bin

main = print $(b 01101001)



{- bin.hs -}

module Bin (b) where

import Language.Haskell.TH

bin :: Integer -> Integer
bin 0 = 0
bin x = bin' x + 2 * bin (div x 10)
    where bin' x = if odd x then 1 else 0

b x = litE $ IntegerL $ bin x

{-
>> ghc --make -fth binmain.hs 
>> ./binmain
105
-