Re: alist-get in Emacs 24?

[Stefan Monnier]

> There was assoc.el in prior Emacsen (and it's still lying around in
> lisp/obsolete).  `aput' is its setter for alists.  Works great, but is
> obsolete.

"Works great" only if your needs are very modest.  E.g. it's
terribly inefficient, and it relies on dynamic scoping.

As for the (gv-define-expander alist-get ...), you could just blindly
copy that definition into your package.  Of course that'll only work for
Emacsen with gv.el.  For older Emacsen, you'll have to use
define-setf-expander, which indeed works a bit differently from
gv-define-expander.  For the very reason that I invented
gv-define-expander, I'd rather not try and come up with the equivalent
define-setf-expander.


        Stefan