From: Drew Adams <drew.adams@oracle.com>
To: Philip Kaludercic <philipk@posteo.net>,
Dr Rainer Woitok <rainer.woitok@gmail.com>
Cc: "help-gnu-emacs@gnu.org" <help-gnu-emacs@gnu.org>
Subject: RE: [External] : Re: (interactive) and &optional
Date: Sat, 25 Mar 2023 14:33:46 +0000 [thread overview]
Message-ID: <SJ0PR10MB5488C5458E78CCF85AE5909CF3859@SJ0PR10MB5488.namprd10.prod.outlook.com> (raw)
In-Reply-To: <87fs9t3rfz.fsf@posteo.net>
> it might also be that you are interning the empty string,
> which creates a symbol with an empty string as the symbol name -- which
> is not unique.
What do you mean by "is not unique"?
> > Does an empty symbol have an external representation like an empty list or string, allowing the use of "eq"?
Yes: ##
(setq foo (intern ""))
C-h v foo
foo's value is ##
(symbolp '##) ; => t
(symbolp foo) ; => t
(symbol-name '##) ; => ""
(symbol-name foo) ; => ""
(setq ## 42) ; or (set foo 42)
(symbol-value '##) ; => 42
## ; => 42
(But note that `C-h v ##' doesn't "work".)
next prev parent reply other threads:[~2023-03-25 14:33 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-23 19:10 (interactive) and &optional Dr Rainer Woitok
2023-03-23 19:20 ` Philip Kaludercic
2023-03-25 12:35 ` Dr Rainer Woitok
2023-03-25 13:12 ` Philip Kaludercic
2023-03-25 14:33 ` Drew Adams [this message]
2023-03-25 15:36 ` [External] : " Dr Rainer Woitok
2023-03-25 16:58 ` Philip Kaludercic
2023-03-23 20:01 ` Emanuel Berg
2023-03-24 9:23 ` Jean Louis
2023-03-24 20:52 ` Philip Kaludercic
2023-03-24 21:07 ` Emanuel Berg
2023-03-27 1:52 ` [External] : " Drew Adams
2023-03-27 2:40 ` John Yates
2023-03-24 21:42 ` Jean Louis
2023-03-26 1:04 ` Emanuel Berg
2023-03-30 19:04 ` Jean Louis
2023-03-25 12:05 ` Dr Rainer Woitok
2023-03-25 14:32 ` Jean Louis
2023-03-25 15:41 ` Dr Rainer Woitok
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