Change nil's to zeroes in elisp

Posted by mageslayer on Stack Overflow See other posts from Stack Overflow or by mageslayer
Published on 2010-05-25T16:38:12Z Indexed on 2010/05/25 16:41 UTC
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emacs

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elisp

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nil

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zero

Hi all

I'd like to ask - what is the function doing nil conversion from nil's to zeroes in elisp?

I'm a newbie and I think I am inventing the wheel with my code:

(defun chgnull (x)
  (if (null x) 0 1))
(mapcar 'chgnull '(1 2 nil))

Search through Emacs sources by keyword "to zero" and such haven't shown anything relevant.

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