Sha256: 89f401cdc95342e4aa53c4ef360ebfb4b4e23b2dac037dc6e24b86f80d757aba
Contents?: true
Size: 739 Bytes
Versions: 62
Compression:
Stored size: 739 Bytes
Contents
module Base (Error(..), rebase) where
import Control.Monad (foldM)
import Data.List (unfoldr)
import Data.Tuple (swap)
data Error a = InvalidInputBase | InvalidOutputBase | InvalidDigit a
deriving (Show, Eq)
rebase :: Integral a => a -> a -> [a] -> Either (Error a) [a]
rebase ibase obase ds
| ibase < 2 = Left InvalidInputBase
| obase < 2 = Left InvalidOutputBase
| otherwise = toDigits obase <$> fromDigits ibase ds
where
fromDigits base = foldM f 0
where
f acc x | x >= 0 && x < base = Right (acc * base + x)
| otherwise = Left (InvalidDigit x)
toDigits base = reverse . unfoldr f
where
f 0 = Nothing
f x = Just . swap $ x `divMod` base
Version data entries
62 entries across 62 versions & 1 rubygems