bug#59820: [PATCH] * nadvice/nadvice.el: support non-symbol (closure/lambda) advices (old Emacs)

[Stefan Kangas <stefankangas@gmail.com>]

daanturo <daanturo@gmail.com> writes:

> This patch provides the ELPA version (for Emacs < 24.4) of nadvice.el's
> advice-add the ability to handle anonymous advices.
>
> I have tested with a simple example:
>
> ```emacs-lisp
>
> (let* ((sym (make-symbol "nadvice λ")))
>   (defalias sym (lambda (&rest args) '(1)))
>   (advice-add sym :around (lambda (func &rest args)
>                             (append (apply func args) '(2))))
>   (vector
>    ;; advised returned value
>    (funcall sym)
>    (progn
>      (advice-remove sym (lambda (func &rest args)
>                           (append (apply func args) '(2))))
>      ;; unadvised returned value
>      (funcall sym))))
>
> ;; => [(1 2) (1)]
>
> ```

Stefan, any comments here?