Pretty class as alternative for Show class
waldmann at imn.htwk-leipzig.de
Wed Feb 13 02:42:48 EST 2008
Henning Thielemann wrote:
> The Show class converts to String, the Pretty class could convert to a
> pretty printer data type like Doc. [...]
Ah yes, I use this since a long time
class ToDoc a where
toDoc :: a -> Doc
toDoc = toDocPrec 0 -- useful?
toDocPrec :: Int -> a -> Doc
I generally make even this output re-readable,
and I'm reading is via Parsec:
class Reader a where
readerPrec :: Int -> Parser a
and I also have the obvious DrIFT rules
that can generate standard instances for most types.
I will happily contribute this code to whatever Pretty class emerges.
(Well, it's free, so I'd have no way to not contribute it ...)
best regards, Johannes.
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