bug#14793: 23.4; Cannot bind a function to a sequence of two mouse keys

[Eli Zaretskii]

> From: Alex <agrambot@gmail.com>
> Cc: 14793@debbugs.gnu.org,  npostavs@users.sourceforge.net,  
> regularclockwork@gmail.com
> Date: Mon, 02 Oct 2017 21:59:37 -0600
> 
> > I just asked that question because my reading of the code is that this
> > is not supported.  Maybe I'm misreading: keyboard.c:read_char is not
> > for the faint at heart.
> 
> Yeah, I'm having trouble going through it. Is there a way to make it
> supported, though? For example, what about catching the error around
> read_char_x_menu_prompt (keyboard.c:L2683) and not exiting if an error
> was thrown?

That's hardly a clean solution.  A clean solution would avoid calling
Fx_popup_menu when it detects the situation we are talking about.

> >> Also, "(emacs) Mouse Buttons" states that "You can put more than one
> >> mouse button in a key sequence, but it isn’t usual to do so.".
> >> 
> >> How would one do this if a mouse click can't be a prefix key?
> >
> > By making a menu, I presume.
> 
> Do you mean those mentioned in "(emacs) Menu Mouse Clicks"? Does
> clicking in those menus count as key sequences?

Yes, of course.  You can see that with "C-h l", for example.  Also,
every non-leaf menu item is a keymap.