Dominic Steinitz wrote:

I often find myself wanting to print out hex values as a string. I couldn't

Me too! And I also often want to see binary values (ie. 13 == 0x0D == 0b1101) Just some information: I remember that there is a 'showHex' function in the "NumExts" module in Ghc (at least in version 5.x). See: http://www.haskell.org/ghc/docs/latest/html/hslibs/sec-NumExts.html All the best, -- Daan.

find a library function so I came up with this. Is it worth putting in a library? The obvious place for me would be Data.Codec.Utils.

Thoughts?

Dominic.

hexify :: Integral a => a -> Doc hexify n = let bar = map (map sh) (split 16 (toOctets 256 n)) foo = map (intersperse colon) (map (map text) bar) baz = vcat (map hcat foo) in baz

sh x | x < 16 = showHex x "0" | otherwise = showHex x ""

split :: Int -> [a] -> [[a]] split n xs = unfoldr (g n) xs where g :: Int -> [a] -> Maybe ([a],[a]) g n y | length y == 0 = Nothing | otherwise = Just (splitAt n y)

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On Sun, Nov 13, 2005 at 01:51:22PM +0000, Dominic Steinitz wrote:

I often find myself wanting to print out hex values as a string.

Me too. I have a functions that formats the data in a similar way that the xxd program does.

I couldn't find a library function so I came up with this. Is it worth putting in a library?

Sure.

Thoughts?

I haven't thought about producing a Doc - good idea.

split :: Int -> [a] -> [[a]] split n xs = unfoldr (g n) xs where g :: Int -> [a] -> Maybe ([a],[a]) g n y | length y == 0 = Nothing | otherwise = Just (splitAt n y)

The first guard, (length y == 0), seems a bit expensive - the whole thing will have a quadratic time and can evaluate the input list too eagerly. Best regards Tomasz