Mail von Nicolas Goaziou, Sun, 04 Jun 2017 at 11:35:34 +0200:
Hello,
> "Stefan-W. Hahn" <stefan.h...@s-hahn.de> writes:
>
> > What I don't understand is, if I expand the pcase with (macrostep-expand) I
> > get the following:
> >
> > ,----
> > | (let (res)
> > | (dolist (pair (buffer-local-variables))
> > | (if
> > | (consp pair)
> > | (let*
> > | ((x
> > | (car pair))
> > | (x
> > | (cdr pair)))
> > | (let
> > | ((val x)
> > | (var x))
> > | (push
> > | (list 'set var val)
> > | res)))
> > | nil))
> > | res)
> > `----
> >
> > And this is obviously wrong.
>
> This is not obviously wrong. You may be thinking that both `x' symbols
> are the same, but they are not. E.g.,
>
> (let ((s1 (make-symbol "x"))
> (s2 (make-symbol "x")))
> (list (list s1 s2) (eq s1 s2)))
>
> =>
>
> ((x x) nil)
This I understand, but cannot see it in the macrostep-expanded code.
I will try learn more to understand this.
So it is obvoius now that you are a lisp magician of 8th grade. :-)
Thanks and kind regards,
Stefan
--
Stefan-W. Hahn It is easy to make things.
It is hard to make things simple.
