Philipp Stephani <p.stephani2@gmail.com> schrieb am Mi., 9. Nov. 2016 um
22:19 Uhr:

>
> For example:
>
> (funcall (lambda (&optional &rest &rest &optional x) (list x)) 'a)
> => ((a))
>
> Obviously here the &rest keyword "wins", but I think that's overly
> confusing.  Such an argument list is most likely a programmer mistake,
> and should signal an error to make the programmer aware of the mistake.
>
>
Here's a patch that detects such argument lists.