RE: Where can I find `aget'

[Drew Adams]

> >> The good old `Symbol's function definition is void:' tells me that
> >> there is no `aget'. Which library contains `aget'?
> >
> > It's in assoc.el.
> 
> Ah, thanks.
> Nevertheless elnode doesn't work. Maybe it has something to do with
> this message?

Could be - dunno.
 
> Loading assoc...done
> Package assoc is obsolete!

AFAIK, assoc.el will be deprecated in Emacs 24 (which is not yet released).

As you saw, the assoc.el code still remains in Emacs, at least for now
(prerelease).  So I would say that it is not yet _effectively_ obsolete, in the
usual sense of the term - in spite of what that message tells you.  Dunno
whether the assoc.el code will in fact remain part of Emacs when Emacs 24 is
released.

Typically, deprecation means that a feature/object might (typically will) become
obsolete (and desupported) at some _future_ time.  Deprecation gives users a
heads-up that becoming obsolete and being desupported might (probably will)
follow at some point.  Deprecation provides a period of backward compatibility
and lets users adapt before losing the feature/object altogether.

My guess is that what is really meant in this case is that assoc.el will be
deprecated (not made obsolete) in Emacs 24, meaning that it might be made
obsolete and desupported in some post-24.1 release.  But you would need to ask
Emacs Dev what they really mean.  

There is anyway some ambiguity in the term "obsolete", which can mean that a
feature/object is no longer in use, no longer useful, or even no longer
fashionable.