Aaron Denney wrote:
On 2007-11-17, Andrew Coppin <[EMAIL PROTECTED]> wrote:
pack8into16 :: [Word8] -> Word16
pack8into32 :: [Word8] -> Word32
unpack16into8 :: Word16 -> [Word8]
unpack32into8 :: Word32 -> [Word8]
pack8into16s :: [Word8] -> [Word16]
pack8into32s :: [Word8] -> [Word32]
etc.
I had to write all these myself, by hand, and then check that I got
everything the right way round and so forth. (And every now and then I
find an edge case where these functions go wrong.)
Well, you know, some of these are really the wrong signatures:
pack8into16 :: (Word8, Word8) -> Word16
pack8into32 :: (Word8, Word8, Word8, Word8) -> Word32
unpack16into8 :: Word16 -> (Word8, Word8)
unpack32into8 :: Word32 -> (Word8, Word8, Word8, Word8)
curry the above to taste.
Yeah, but
unpack16into8s = concatMap unpack16into8
;-)
Now if you just define some function splitN :: Int -> [x] -> [[x]] (I'm
sure we've debated why this isn't defined already...), we can even write
pack8into16s = map pack8into16 . splitN 16
And so we continue...
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