Re: About `macroexpand'

[Xue Fuqiao]

On Sun, 30 Dec 2012 07:50:45 +0400
Filipp Gunbin <fgunbin@fastmail.fm> wrote:

> The comparison doesn't make any sense and what
> is actually overwritten is the local value of `variable'.

I still don't understand.  I tried this:
(defmacro t-becomes-nil (variable)
  (list 'if (list 'eq variable t)
      (list 'setq variable nil)))
(setq foo t)
(macroexpand '(t-becomes-nil foo))

But it returns (if (eq foo t) (setq foo nil)))
What's the difference between these two macros?
-- 
Best regards.