Re: Font-lock in COMINT modes

[Chong Yidong]

Richard Stallman <address@hidden> writes:

> I listed in FOR-RELEASE that this case is slow:
>
>     You must have gotten that impression from Stefan's 12/08 message:
>
>       if [font-lock-defaults ] is nil font-lock-mode-internal is not
>       activated at all.  AFAIK nil and (nil t) are equivalent (i.e. don't
>       highlight anything), except that (nil t) takes a lot more CPU to do
>       nothing (it runs all the font-lock-foo-function hooks, enables
>       jit-lock so as to do nothing just-in-time rather than eagerly,
>       checks where nothing needs to be done, rounds up to a whole number
>       of lines the region upon which inaction is requested, checks if
>       there's a multiline entity and extends the region even more, so that
>       nothing is done in a multiline way, ...).
>
>     Even though it is true that font lock jumps through more hoops with
>     (nil t), there is no evidence that this slowdown affects the user.
>
>
> Could you check and see?

I haven't been able to observe any slowdown when font-lock-defaults is
(nil t).  Not surprising, since I don't notice any slowdown when
font-lock-defaults is (something t), i.e. normal font-lock situations!

Maybe someone running on a 486 can observe a difference, who knows.