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Subject: Re: A value for "nothing"
Date: Mon, 27 Aug 2018 22:54:03 +0200
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To: Mark H Weaver <mhw@netris.org>
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> On 27 Aug 2018, at 22:12, Mark H Weaver <mhw@netris.org> wrote:
> 
> More generally, even for people only interested in supporting Guile, if
> they would like their libraries to be usable from Elisp code on Guile,
> which may become important some day if Guile-Emacs matures, then it's
> problematic to use #nil for anything that needs to be distinguished from
> '() or #f.

Maybe you need an addition: an empty value.