bug#50999: 29.0.50; Deleting libraries obsolete since Emacs 24

[Phil Sainty <psainty@orcon.net.nz>]

On 2021-10-06 01:27, Eli Zaretskii wrote:
> It could be that some items on the list need to get special treatment
> for some valid reasons, or perhaps because we've learned something new
> since they were obsoleted.

One such case is longlines.el -- I'd like this to not only be retained,
but also be restored to non-obsolete status.

This was marked obsolete in 24.4 on the basis that visual-line-mode
provided a better alternative, and indeed visual-line-mode is better
for wrapping lines of normal lengths; however longlines-mode is
actually very valuable for editing files with lines that are so long
that they cause performance problems.  This is because longlines-mode
converts the long lines into short lines for editing, and therefore
it will give you good performance at *any* position in the file.

For this reason, so-long.el has supported longlines-mode as a standard
action since version 1.0.  While so-long-mode is very fast to enable,
it still won't cope well if you move point deep into an incredibly long
line.  Conversely longlines-mode is slow to enable (as it has to break
all the long lines), but it then gives good performance everywhere in
the buffer.  As such they complement one another (and you can switch
between them via the "So Long" menu).


-Phil