Re: [External] : Re: Testing whether a list contains at least one non-nil element

[Emanuel Berg]

Michael Heerdegen wrote:

>> If you are doing it "by hand", why not indulge in Lisp's
>> "classic elegance", like so:
>>
>>   (defun has-non-nil (lst)
>>     (cond
>>      ((null lst) nil)
>>      ((consp lst) (or (not (null (car lst))) (has-non-nil (cdr lst))))
>>      (t (error "Not a proper list! You cheater!"))))
>
> You don't want to implement such functions in Emacs with
> recursion because you'll easily hit `max-lisp-eval-depth'
> when they are called. Sorry to tell you, but a loop is the
> preferable way in Elisp.

He knows that ...
>
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