[Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Evan Laforge
I've been trying to get my head around the Wadler-Leijen pretty printing combinators for a while now and having some trouble. Specifically, I have trouble getting them to pick optimal line breaks. The existing combinators like 'sep' (and everything built from it) merge all elements with $ and

Re: [Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Stephen Tetley
A quick suggestion - does setting the ribbon_frac to something like 0.8 improve things? The Show instance for wl-pprint's Doc uses 0.4 which I've found too low. This means you'll have to write your own display function using `renderPretty`... ___

Re: [Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Ivan Lazar Miljenovic
On 20 March 2012 20:24, Stephen Tetley stephen.tet...@gmail.com wrote: A quick suggestion - does setting the ribbon_frac to something like 0.8 improve things? The Show instance for wl-pprint's Doc uses 0.4 which I've found too low. This means you'll have to write your own display function

Re: [Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Stephen Tetley
Ahem - there was a severe typo in my last message. Usually I wouldn't spam the list to repair my failings but edit distance on the error in that message was so large it made no sense at all. printing that cannot be undone by `group`, or the combinators that use group are given more long-winded

Re: [Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Evan Laforge
On Tue, Mar 20, 2012 at 2:24 AM, Stephen Tetley stephen.tet...@gmail.com wrote: A quick suggestion - does setting the ribbon_frac to something like 0.8 improve things? Nope. The ribbon (IMO both an undescriptive name and underdocumented) only constraints the number of non-indent characters per

Re: [Haskell-cafe] HughesPJ vs. Wadler-Leijen

2012-03-20 Thread Evan Laforge
On Tue, Mar 20, 2012 at 6:52 AM, Stephen Tetley stephen.tet...@gmail.com wrote: Hi Ivan I haven't found any bugs in WL, however I do find the API somewhat confusing regarding line breaking (I would need to consult the manual to tell you the difference between linebreak, softline etc.). This