Re: Incompatible change without "warning"

[Nick Roberts]

 >     I'd prefer to define the same `define-obsolete-variable-alias' macro as
 >     used in XEmacs.
 > 
 > That sounds useful.

Does this DTRT?

(defmacro define-obsolete-variable-alias (symbol aliased
                                                 &optional docstring when)
"Make SYMBOL a variable alias for symbol ALIASED and warn that
SYMBOL is obsolete. If provided, WHEN should be a string
indicating when the variable was first made obsolete, for example
a date or a release number. Fourth arg docstring, if non-nil, is
documentation for symbol."
  (list 'progn
        `(defvaralias ,symbol ,aliased ,docstring)
        `(make-obsolete-variable ,symbol ,aliased ,when)))

The version in XEmacs may be better but I've not looked at at it deliberately,
as I wasn't sure of the implications of copying it.

Nick