ajb:
> Quoting tom <[EMAIL PROTECTED]>:
> This looks cool:
>
> bytes2int = foldr ((. (256 *)) . (+)) 0 . (map toInteger)
>
> but I'm not smart enough to parse it. This is both more readable and
> shorter:
>
> bytes2int = foldr (\x r -> r*256 + fromInteger x) 0
>
> Integer log2's are probably better done using integers only, or at least
> abstracted out into a separate function.
Reminds me of this code from Data.Binary:
unroll :: Integer -> [Word8]
unroll = unfoldr step
where
step 0 = Nothing
step i = Just (fromIntegral i, i `shiftR` 8)
roll :: [Word8] -> Integer
roll = foldr unstep 0
where
unstep b a = a `shiftL` 8 .|. fromIntegral b
Which is a bit stream-fusion inspired, I must admit.
-- Don
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