RE: master 8f0f851: * lisp/autoarg.el: Use lexical binding.

[Drew Adams <drew.adams@oracle.com>]

> > I don't think I understand the original warning though.

Same here.

> > This minimized code example gives me "Unused lexical
> > variable 'i'" when byte-compiled:
> >
> > (let (alist)
> >   (dotimes (i 10 alist) (push i alist)))
> 
> It's unused in the expression `alist`.

So?  (defun foo (a) (message "%s" a) 42) doesn't use
`a' in the value returned.  We don't warn about that,
do we?

> If you don't use `i` there, then you should do:
> (let (alist)
>   (dotimes (i 10) (push i alist))
>   alist)

Doesn't seem right to have such a distinction.  Is
this just an implementation artifact (essentially a
bug), or is there a good reason for the warning in
the first case (and not in the second)?

FWIW, all that Common Lisp says about its `dotimes'
in this regard is this:

"At the time result-form is processed, VAR is bound
to the number of times the body was executed."

Why should we warn, if the result form doesn't use
the variable?