bug#18367: 24.4.50; [PATCH] Text property `font-lock-ignore', to protect from font-lock

[Wolfgang Jenkner]

On Mon, Sep 01 2014, Eli Zaretskii wrote:

>> From: Wolfgang Jenkner <wjenkner@inode.at>
>> Date: Mon, 01 Sep 2014 20:45:58 +0200
>> Cc: 18367@debbugs.gnu.org
>> 
>> On Sun, Aug 31 2014, Drew Adams wrote:
>> 
>> > (elisp) `Other Font Lock Variables' says this about it:
>> >
>> >  Variable: font-lock-extra-managed-props
>> >  This variable specifies additional properties (other than
>> >  `font-lock-face') that are being managed by Font Lock mode.  It is
>> >  used by `font-lock-default-unfontify-region', which normally only
>> >  manages the `font-lock-face' property.  If you want Font Lock to
>> >  manage other properties as well, you must specify them in a
>> >  FACESPEC in `font-lock-keywords' as well as add them to this list.
>> >  *Note Search-based Fontification::.
>> 
>> I think `font-lock-face' is a typo here (it should read `face').
>> 
>> It is clear from looking a the code (or doing some experiments) that
>> font-lock-default-unfontify-region doesn't remove the `font-lock-face'
>> property.
>
> The "it" in that text alludes to font-lock-extra-managed-props, not to
> font-lock-face.

I don't think the "it" is a problem here.

>  After all, the former is what is being documented in
> the text you cited; the latter is just mentioned because
> font-lock-face is another kind of specification of "additional"
> properties of interest to Font Lock.

But, `font-lock-face' is of no interest to
font-lock-default-unfontify-region, the `face' property is.

font-lock-default-unfontify-region does not remove the `font-lock-face'
property, it removes the `face' property.

font-lock-default-unfontify-region does not "manage" the
`font-lock-face' property, it "manages" the `face' property.

Sorry, for saying three times the same thing, but Drew cited this part
of the manual and it seems to be the reason why Stefan's request didn't
make sense to him.

Wolfgang