blob: 655f593f0143918e959bb0f9f77b678dd57ac30e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
module Data.BaseConvert (toString, toNum, toAlphaDigit, fromAlphaDigit) where
import Data.Sequence
import Data.Foldable (toList)
import Data.List
import Data.Char
digit_alphabet :: [Char]
digit_alphabet = ['0'..'9'] ++ ['A'..]
toBase :: (Integral a) => a -> a -> [a]
toBase _ 0 = [0]
toBase b v = toList $
unfoldl (\n -> if n == 0 then Nothing else Just (n `divMod` b)) v
toAlphaDigit :: (Integral a) => a -> Char
toAlphaDigit = (digit_alphabet !!) . fromIntegral
toString :: (Integral a) => a -> a -> String
toString b v = map toAlphaDigit (toBase b v)
fromAlphaDigit :: (Num a) => Char -> a
fromAlphaDigit v = fromIntegral n
where Just n = elemIndex (toUpper v) digit_alphabet
fromBase :: (Num a) => a -> [a] -> a
fromBase b = foldl (\n k -> n * b + k) 0
toNum :: (Num a) => a -> String -> a
toNum b v = fromBase b (map fromAlphaDigit v)
|
