Re: so-long-mode and line-move-visual

[Phil Sainty]

On 2022-05-08 23:20, Eli Zaretskii wrote:
> > With the option combo currently set by so-long, Emacs is only
> > displaying a small portion of a long line
>
> When truncate-lines is nil, lines are NOT truncated, so long
> lines wrap around, and we display whole lines (at least their
> parts that fit in a window, and windows nowadays tend to be very
> tall), not their small portions.  What am I missing?

I think you're only missing the sheer scale of the line lengths I
am referring to when I say that -- even if tall, an entire window
can *easily* be completely filled by only "a small portion" of the
kind of line I'm trying to protect against (for the example I gave
before, the line is 18 megabytes of JSON).


> > As such, I don't think these defaults should be changed.
>
> Well, I found the defaults sub-optimal in the case someone
> presented on help-gnu-emacs yesterday, thus my question.

I'm not subscribed to help-gnu-emacs but I can see the thread in
the archives.  At first glance so-long does what it's supposed to
do with that symbol.ts file.  The description of the problem is a
bit vague, and I don't know why they'd see different performance
from the minor mode vs the major mode (the major mode for *.ts
files would presumably need to be causing the slowness directly,
but that would be unusual).  Alternatively, perhaps they're using
the "Doom Emacs" config which may still be enabling `font-lock-mode'
in `so-long-minor-mode' (which I told them was a bad idea when I
first became aware, but I don't think they changed it).

I can see that the user in question has had success with using
`longlines-mode', which does seem like a good solution for them.


> If you are still unconvinced, so be it.

I am.  I do appreciate that the defaults aren't ideal for all
cases, but I nevertheless believe they're the right defaults, as I
don't believe there's any particular collection of settings which
is optimal in all situations.  My overriding concern is preventing
Emacs from ever locking up due to merely visiting a file, so that
goal has always informed the default settings.


-Phil