Re: [PATCH] Renaming non-X x_* identifiers

[Alex Gramiak <agrambot@gmail.com>]

Eli Zaretskii <eliz@gnu.org> writes:

> Not sure I understand what you mean by "policy".  Rebasing or not in
> general is up to you, but maybe you are asking about something more
> specific.

I mean specifically about rebasing during the review process. Though it
turns out that the Savannah git server doesn't allow this, so I just
deleted and repushed the entire branch instead.

> If every window-system is required to provide these hooks, then I
> think it will be enough to test only those which also have
> implementations on TTY frames.

Okay. How about wrapping the required hooks in termhooks.h in #ifdef
HAVE_WINDOW_SYSTEM so that terminal-only builds that erroneously have
these hooks in their scope issue a compiler error?

>> >>  	  store_frame_param (f, prop, val);
>> >>  
>> >> -	  param_index = Fget (prop, Qx_frame_parameter);
>> >> +	  param_index = Fget (prop, Qframe_parameter_pos);
>> >
>> > The x-frame-parameter property is visible from Lisp, no?  You are here
>> > replacing it with a different symbol, which is a backward-incompatible
>> > change.
>> 
>> While it is visible from Lisp, I don't see why anyone would change it
>> considering that AFAIU it's used as an internal value in frame.c.
>> frame.c sets it and uses the value of the property to call the
>> appropriate element in frame_parm_table, which Lisp-code should not rely
>> on.
>> 
>> Then again, apparently cedet/semantic/util-modes.el accesses this
>> property, but that could be changed.
>
> Anything that gets put into frame-parameters can have some Lisp out
> there using it.  So I think we have 2 alternatives:
>
>   1) leave those symbols alone
>   2) declare them obsolete, but meanwhile put both the new and the old
>      symbols into frame-parameters
>
> The above assumes that if a Lisp program does something with one of
> these parameters, that will have no effect, i.e. that these parameters
> are one-way communications from the Emacs internals to Lisp, as far as
> Lisp programs are concerned.  If the communications are two-way, then
> I don't see how we can change these names; do you have any ideas?

AFAIU it's technically possible that someone could use `put' to set a
new value, but that's tantamount to changing the internal definition of
the frame parameter setter to another frame parameter setter, so I don't
think such a use case should really be considered.

I don't have any other ideas, but 2) doesn't sound terrible as long as
it would be removed some day. Though I don't feel strongly about the
symbols here.

> It's okay to do that in a followup, but please do that soon.  I don't
> want to risk leaving an unfinished job in the sources.

I just pushed commits implementing this hook and the other one
discussed.

> I think using image_* for all the functions in image.c would be
> better.

Okay, done.

>> >> -	(f, Qx_set_fullscreen, 0, 0, list2 (old_value, fullscreen));
>> >> +	(f, Qgui_set_fullscreen, 0, 0, list2 (old_value, fullscreen));
>> >
>> > This is also visible from Lisp, right?  So renaming the symbol would
>> > be an incompatible change.
>> 
>> I believe frame_size_history_add only uses the symbols as a
>> visual/debugging aid, so I don't believe this is, meaningfully, an
>> incompatible change.
>
> Are they in frame-parameters?  If so, they are visible.

No, but they are used in the variable frame-size-history which is used
by frame--size-history. I'm not sure if this is significant enough to
warrant leaving it alone.

>> >> diff --git a/src/menu.h b/src/menu.h
>> >> index 0321c27454..4412948224 100644
>> >> --- a/src/menu.h
>> >> +++ b/src/menu.h
>> >> @@ -47,14 +47,17 @@ extern widget_value *digest_single_submenu (int, int, bool);
>> >>  #if defined (HAVE_X_WINDOWS) || defined (MSDOS)
>> >>  extern Lisp_Object x_menu_show (struct frame *, int, int, int,
>> >>  				Lisp_Object, const char **);
>> >> +extern void x_activate_menubar (struct frame *);
>> >>  #endif
>> >>  #ifdef HAVE_NTGUI
>> >>  extern Lisp_Object w32_menu_show (struct frame *, int, int, int,
>> >>  				  Lisp_Object, const char **);
>> >> +extern void w32_activate_menubar (struct frame *);
>> >>  #endif
>> >>  #ifdef HAVE_NS
>> >>  extern Lisp_Object ns_menu_show (struct frame *, int, int, int,
>> >>  				 Lisp_Object, const char **);
>> >> +extern void ns_activate_menubar (struct frame *);
>> >
>> > Since you introduced activate_menubar_hook, why do we need to declare
>> > prototypes for its implementation on menu.h, which is a
>> > system-independent header?
>> 
>> The implementations are defined in the *menu.c files, but are added as
>> terminal hooks in the *term.c files.
>
> I'm not sure I understand the answer.  I didn't ask about the
> implementations, I asked about the prototypes.  Since these are hooks,
> their names are not visible outside the corresponding *term.c file,
> right?  Then why do we need the prototypes of w32_activate_menubar,
> ns_activate_menubar, etc. in menu.h?

The declarations are to make the names visible to *term.c. *menu.c
contains the actual definitions, so *term.c needs declarations to set
the hook. It's why *_menu_show are there as well, even though they are
terminal hooks.