Subject: Re: bug#17657: pretty-print #:width values above 49 don't work?

From: Andy Wingo <[email-masked]>
Date: Tue, 21 Jun 2016 16:47:20 +0200

Hi :)

On Sun 01 Jun 2014 20:40, Mark H Weaver <[email-masked]> writes:

> Mark Polesky <[email-masked]> writes:
>> Neither example below should be line-wrapped, but the second one 
>> is.
>
> Our pretty printer, inherited from SLIB and originally written by Marc
> Feeley, uses a great many heuristics to make formatting decisions.
> These heuristics are undocumented and subject to change.
>
> One of its heuristics is that individual expressions shall not be more
> than 49 columns wide.  Notice that pretty-print.scm includes the
> following internal definition:
>
>   (define max-expr-width 50)
>
> (although in fact the maximum width ends up being 49)
>
>> Is there a workaround?
>
> A couple of years ago I added an undocumented #:max-expr-width keyword
> argument to pretty-print, in order to improve the formatting of
> psyntax-pp.scm.  You could use that.

Just pushed some documentation, so this bug is done.

> It would be good to redesign and rewrite our pretty-printer from scratch
> at some point.

Yes!

Andy