bug#30393: 24.4; cperl-mode: indentation failure

[Alan Mackenzie <acm@muc.de>]

Hello, Eli.

On Mon, Mar 05, 2018 at 18:14:51 +0200, Eli Zaretskii wrote:
> > Date: Mon, 5 Mar 2018 08:42:55 +0000
> > From: Alan Mackenzie <acm@muc.de>
> > Cc: 30393@debbugs.gnu.org, Dmitry Gutov <dgutov@yandex.ru>,
> > 	Noam Postavsky <npostavs@users.sourceforge.net>

> > Existing C functions have been modified as follows:
> >   o - signal_after_change.
> >     * - Regardless of the settings of the change hooks,
> >       syntax-ppss-flush-cache will be called for an actual textual
> >       change.
> >   o - Fset_syntax_table.
> >     * - If the new table is literally different from the old,
> >       syntax-ppss-flush-cache will be called with an argument of -1.
> >   o - Fmodify_syntax_entry.
> >     * - If the new entry is literally different from the old one,
> >       syntax-ppss-flush-cache will be called with an argument of -1.
> >   o - init_syntax_once and syms_of_syntax.
> >     * - Administrative amendments.
> >   o - set_properties, add_properties, remove_properties.  If a
> >     syntax-table property set or removed, whether directly or via a
> >     category property, potentially alters the parsing of literals,
> >     syntax-ppss-flush-cache will be called.

> Any reason why you introduce 2 new primitives that no Lisp code uses?

[ Already answered ].

> In any case, this needs documentation changes if and when it's agreed
> upon.

Can we start moving forward with this change, please?

Just a quick summary of what it's about:  syntax-ppss is now being used
in back_comment.  syntax-ppss's cache, at the moment, isn't being
invalidated when the syntax table is swapped, or an entry in it is
changed, or when a syntax-table text property is applied to a buffer
element.  The patch fixes this, as far as back_comment is concerned.

> Thanks.

-- 
Alan Mackenzie (Nuremberg, Germany).