bug#11934: 24.1; provide variable for pp.el to control max display width

[Michael Heerdegen <michael_heerdegen@web.de>]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> I agree.  What pp does now with simple lists isn't optimal.

AFAICT pp.el could be extended easily for handling this problem.

pp is currently very simple - see `pp-to-string'.  It does just `prin1'
(which does most of the work already) the object into a temp buffer.
Then it does some simple cleanups: `pp-buffer'.  That would be the
function to extend (Drew, wanne give it a try?).

But of course handling this problem is not trivial: we can't distinguish
"simple lists" from code, and what might look good for the first might
look weird for a macro call with a special lisp-indent-function value
(e.g. imagine a `defun' call with a line break inserted just after
"defun").

Another challenge is what to do if we have already nearly exhausted the
width limit.


Michael.