Re: Toggling the reverse frame parameter

[Pascal J . Bourguignon]

Ben Key <bkey76@gmail.com> wrote:
> Hello,
> 
> I like the reverse video mode of Emacs sometimes, but not always.  I
> would like to have a way of toggling this property without having to
> restart Emacs (right now the only way of setting this property is to
> start Emacs with or without the -rv command line argument).  I have tried
> M-: (set-frame-parameter (selected-frame) 'reverse t) to turn it on and
> (set-frame-parameter (selected-frame) 'reverse nil) and M-:
> (set-frame-parameter (selected-frame) 'reverse nil) to turn it off, but this 
> does not work.
> 
> Does anyone have any suggestions or is the reverse video effect something
> that can only be specified at start up?
> 
> Thanks.


I don't have access to emacs right now, so I would suggest a way to find
out by yourself: use the sources Luke!

Fetch the sources of emacs from
ftp://ftp.gnu.org/gnu/emacs/emacs-23.3.tar.gz
extract them from the archive, search for the main function, follow it to
the processing of the command line argument -rv. Identify the action
realised (setting of some variable or call to a function to configure the
reverse), and then grep the sources to see if this variable or function is
used somewhere else and if you can call it from an emacs lisp function.

It is possible that the last step is not implemented.  Then you can add it,
add an emacs lisp builtin function to toggle the reverse from lisp, and
compile the new emacs.



-- 
__Pascal J. Bourguignon__