Re: Speed of keyboard macro execution?

[Eli Zaretskii <eliz@gnu.org>]

> From: Achim Gratz <Stromeko@nexgo.de>
> Date: Thu, 10 Dec 2015 19:15:53 +0100
> 
> Eli Zaretskii writes:
> > After all, how frequently do you need to edit files with lines in
> > excess of 11K characters?
> 
> If editing includes just opening the file and navigating around most of
> the time, then the answer to that question for me is "daily".

Yes, some of us do that a lot (myself included).  But not most of us.

> I can guarantee that there are no multi-byte or non-printing
> characters in those files if that would make a difference.

No, it doesn't help.  Detecting a pure-ASCII buffer is very easy, so
if this would help, we would be using it long ago.

The main problem, in a nutshell, is that to get to the next visual
line, you need to traverse all the characters of the preceding line.
Going backward (which happens every time you type C-p, and also many
times behind the scenes, e.g., when Emacs needs to determine where to
set the window start for next redisplay) is even more problematic,
since Emacs can currently only do that by starting from the beginning
of the previous _physical_ line (there's an optimization in this
regard for preposterously long lines, but it loses accuracy -- it
could cause horizontal scrolling when you move point vertically).