On Sat, Aug 29, 2009 at 3:22 PM, Michael Mossey
For debugging purposes I'm interested in pretty-printing data; to start with, lists of algebraic data types. Basically I'd like 'show' with the ability to put each entry of a list on a separate line, and indented. Note that the algebraic data might have an inner list as one of its elements, so this is a non-obvious formatting problem.
I believe I can make instances of Show, can I not? Is there something called showList which I can use to code my own method of showing lists of a particular type? My understanding is that I can't make [a] an instance of Show; hence they provided showList.
So basically, I'm wondering if a pretty-printing (for data!) library already exists, or whether I should try to make instances of Show.
Take a look at the pretty-printing libraries available on Hackage. I've personally used two of them, pretty and wl-pprint. I'm fairly sure both of them define pretty-printing for lists, but I don't know whether it's done the way you want. /M -- Magnus Therning (OpenPGP: 0xAB4DFBA4) magnus＠therning．org Jabber: magnus＠therning．org http://therning.org/magnus identi.ca|twitter: magthe