Re: [rudalics@gmx.at: Re: jit lock sit-for provokes redisplay provokes imenu]

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> Better yet, introduce a macro `with-buffer-unmodified' like the one used in
>> jit-lock, and make it manage a `buffer-really-modified-tick', kind of like
>> the buffer-chars-modified-tick.  Then use it in jit-lock/font-lock
>> and friends.

> I don't see how this could possibly work.  We can't update
> buffer-really-modified-tick in Lisp code for arbitrary buffer changes
> (that's the whole point of Martin's patch --- you have to do it at the
> C level).  And you can't use it to manage a general-purpose variable
> like imenu-menubar-modified-tick, because that keeps track of the
> value of (buffer-modified-tick) as of the last call to
> `imenu-update-menubar', so imenu must reset
> imenu-menubar-modified-tick during each call to
> `imenu-update-menubar'.

It can manage a variable that keeps track of a pair of numbers, that say
"any buffer-tick values between those two numbers can be considered as
equal".


        Stefan