bug#45652: so-long mode not triggered despite big file with very long lines

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Mon, 11 Jan 2021 22:07:20 +0100
> Cc: 45652@debbugs.gnu.org,
>  積丹尼 Dan Jacobson <jidanni@jidanni.org>
> 
> Lars Ingebrigtsen <larsi@gnus.org> writes:
> 
> > I can give writing something like that a shot...  It could return, say,
> > the length of the longest line, and the number of lines?  The median
> > line length would be nice, but would be slower.
> 
> Mean would be easy, and standard deviation would be possible (but
> require two passes, I guess?)

There are algorithms that don't require 2 passes.  Let me know if you
need me to describe something like that.