Re: emacs rendering comparisson between emacs23 and emacs26.3

[Dmitry Gutov]

Hi Alan,

On 07.04.2020 20:42, Alan Mackenzie wrote:

> > Scenarios that are made slower if the file is large are probably caused
> > by the same architectural decisions that make (find-file "src/xdisp.c")
> > slow-ish. All those could likely be improved if CC Mode migrated to
> > using syntax-propertize-function, with its on-demand approach to parsing.
>
> Please would you stop saying this.  It's not true, and it gets very
> wearing.  The crude syntax-propertize-function mechanism would have to
> be considerably enhanced before it could support CC Mode's features.

I will shut up about it now (saying it twice it plenty), but I am pretty 
confident saying that if you manage to migrate to s-p-f, file opening 
time will go down. Performance while typing is likely to improve too, at 
least when the same buffer is not shown in another window, many thousand 
lines later. It's not a given, but I'd really like to see you try 
collaborating with Stefan. At least for a prototype, to have a better 
idea of the associated performance tradeoffs. He posted a preliminary 
patch in the past, FWIW.

"Considerable enhancement" can also be a part of that discussion.

> And even then, it would be unlikely to be faster than the current CC
> Mode.

Some scenarios can become slower, that's for sure. But the more common 
ones can get faster. We won't know until we try.