Re: [Committed PATCH] Re: cc-mode fontification feels random

[Alan Mackenzie]

Hello again, Stefan.

I've committed a corrected version, after my commit from Friday caused
Emacs to hang for several minutes.  It probably wants a NEWS item.
Otherwise, I'm hoping it won't be noticed (except by Eli, of course ;-).

"Found types" should now be systematically and correctly fontified, even
if it takes a short while after starting the major mode.

On Fri, Oct 22, 2021 at 20:13:25 +0000, Alan Mackenzie wrote:
> On Tue, Aug 31, 2021 at 21:17:12 +0000, Alan Mackenzie wrote:
> > On Tue, Aug 31, 2021 at 14:56:13 -0400, Stefan Monnier wrote:
> > > > So, it seems I want something like stealth, but not quite.  How about,
> > > > say jit-lock-single-fontification - it would apply to individual buffers
> > > > only, would scan through the buffer precisely once, and would do just
> > > > enough 500-byte chunks at at time to take 0.05 seconds (configurable).

> [ .... ]

> > It is the incorrectness of the display of some CC Mode types, rather
> > than the speed of fontification which is the issue here.

> [ .... ]

> > It may be busy, but it remains responsive, as in stealth fontification.
> > Is this really a problem, as long as one's running on mains power, not a
> > battery.

> > > For my own use, the benefit of "correct" highlighting of types is not
> > > worth any effort at all.

> > I envisage this facility being enabled by a user option.

> Indeed, though the option is "opt out" rather than "opt in".  This
> facility is only active for a few seconds after initialising a CC Mode
> mode.

> [ .... ]

> > > .... but if so I think you'd be better off running an ad-hoc timer
> > > that does nothing else than scan for type declarations (without doing
> > > the rest of font-lock).  It'll be faster and you won't need to care
> > > about what jit-lock does.

> > Thanks, that's a brilliant idea!  It will be somewhat faster rather than
> > much faster (because parsing declarations is what sucks up the time in
> > CC Mode's fontification), but as you say, assuming most parts of most
> > buffers never get displayed, it will be a net win.

> > It will be more work to code up, though.  I'm currently quite some way
> > into hacking up jit-lock-single-fontification, so I'm going to get that
> > working first to see how well it works.

> I never finished this.  It doesn't matter any more.

> > Then I'll hack up your idea, and confirm it works better.

> Well, I've coded it up and committed it to master.  The fontification of
> CC Mode types should now be somewhat less random than previously.

> > >         Stefan

-- 
Alan Mackenzie (Nuremberg, Germany).