Re: flet, cl-flet, cl-letf in 24.3

[Andreas Röhler]

Am 22.04.2013 15:32, schrieb Stefan Monnier:
> > as reported here [5], this documentation does not really tell me what to do
> > if I want to keep relying on the dynamic scoping of flet.  A brief google
> > search [6] leads me to believe that
>
> >      (cl-letf (((symbol-function 'foo) #'(lambda (...) ...))) ...)
>
> > is the suggested solution,
>
> That's the case.
>
> > Does that always have dynamic scope?
>
> How could it not?
>
> > however I wanted to make sure that is the case.
>
> Even better in most cases is:
>
>       (defvar my-enable-foo-advice nil)
>       (defadvice foo (...)
>         (if my-enable-foo-advice ... ...))
>
> and then replace (flet ((foo ...)) ...)
> with (let ((my-enable-foo-advice t)) ...)
>
>
>          Stefan

Hi Stefan,

until now, a let bound variable was easy to use, there was no difficulty wrt 
global namespace.
From this would expect some confusion, as a defvar is Emacs-wide. Isn't a 
defvar setting init-value only at first time?

I.e. if another program already used (defvar my-enable-foo-advice 
'my-init-value)
 (defvar my-enable-foo-advice nil) should have not effect.

May someone point me to the thread where that was discussed?

Thanks,

Andreas