[Python-ideas] 80 character line width vs. something wider

[Aaron Rubin]

Good stuff, Jess.  It should be easily observed...what percentage of wrapped
lines in the stdlib would end at <=100 characters vs. <=120 vs. <=140, etc?
That would be great facts to know... (don't currently have the time to
analyze the stdlib)

In a quick analysis of my code base (easier to analyze since it is not
wrapped already at 80 or so), I find that roughly 70% of the long lines end
at <=100 and 90% end at <=120.  That's a much steeper slope than you
predicted.  The question I'm faced with is whether the extra 20% of 120 vs.
100 is worth it.

On Fri, May 22, 2009 at 8:00 AM, Jess Austin <jess.austin at gmail.com> wrote:

> On Thu, May 21, 2009 at 3:45 PM, Aaron Rubin
> <aaron.rubin at 4dtechnology.com> wrote:
> > On Thu, May 21, 2009 at 12:28 PM, Jess Austin <jess.austin at gmail.com>
> wrote:
> >> On Thu, May 21, 2009 at 1:01 PM,  Aaron Rubin
> >> <aaron.rubin at 4dtechnology.com> wrote:
> >> > subjective ones.  Arguing over *how* to break lines is actually a
> pretty
> >> > strong argument that time is wasted spent on such issues.  A longer
> line
> >> > width would reduce these arguments, since less would need to be
> wrapped.
> >>
> >> This is an unsupported, and IMHO largely incorrect, assumption.
> >> Several correspondents have noted that they most often overrun their
> >> intended line length by one or two characters.  Just as there's
> >> nothing magical about the number "80", there's nothing magical about
> >> "81" or "82" either.  In a regime of 90-character lines, the limit
> >> will most often be exceeded by one or two characters.  The same will
> >> happen in a regime of 100-character lines, etc.  We'll still need to
> >> break lines, and wrapping them in parentheses will still be the best
> >> way to do that.
> >
> > How can you argue that it wouldn't create *less* line wrapping?
> According
> > to your argument having 10,000 character width lines wouldn't create less
> > line wrapping either.  Nobody ever said it would eliminate it, just
> reduce
> > it.
>
> My point is that line length is a habit of programming.  Like any
> habit, it is largely determined by the context in which it arises.
> Different contexts will yield different habits.  I'll accept your
> implication that there are some idioms that will never take more than
> 100 (is that the number you like?) characters regardless of the
> verbosity of the programmer, and I'll further stipulate an inverse
> linear relation between line length and line-breakage rate.  However,
> I'm pretty confident that this relation has a _very_ shallow slope, so
> that if we assume 10% line breakage at 80 characters, I'd expect 9%
> line breakage at 100 characters.  Is a 1% absolute benefit really
> worth any argument at all?
>
> I doubt you can disprove my slope estimate, but if you try please
> understand how few projects in the wild are completely accepting of
> excessive line length, and base your statistics only on programmers
> who primarily code in those environments.  If you succeed in
> overthrowing heaven and earth here, you'll change programming
> environments and habits for everyone.
>
> Jeremiah's point concerning argumentation rates is also valid.
>
> cheers,
> Jess
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-ideas/attachments/20090522/730e49d3/attachment.html>