bug#8415: 23.3.50; Extensible Emacs Registers

[Leo]

On 2011-04-05 21:50 +0800, Stefan Monnier wrote:
>>> The end point is pretty much the same, but all the intermediate steps
>>> are safe and easy to check.
>> I think a structure still is a better approach.
>
> I already agreed in the previous message.
>
>
>         Stefan

Sorry if I have missed that.

The alternative you propose, i.e. making the value a structure is
actually the first approach I attempted in
http://article.gmane.org/gmane.emacs.devel/137781.

1. all existing register-creating commands need to use the new
   implementation, so the patch won't be any smaller.

2. needs explicitly creating a register-value struct i.e.
  (register-set ?a (register-value-make ....)). If change
  register-set to implicitly convert to a struct then it has
  the same incompatible change as I proposed in this bug report.

So the alternative doesn't offer anything better.

If you are agreeable to the patch in
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8415#19, I am ready to
watch closely for any incoming bugs that related to register.el and fix
them as quickly as I can.

Leo