From: Stephen Berman <stephen.berman@gmx.net>
To: Christopher Monsanto <chris@monsan.to>
Cc: Juri Linkov <juri@jurta.org>,
Stefan Monnier <monnier@iro.umontreal.ca>,
emacs-devel@gnu.org
Subject: Re: power set (Re: Modified keypad keys)
Date: Mon, 01 Oct 2012 11:07:26 +0200 [thread overview]
Message-ID: <87haqeef1t.fsf@rosalinde.fritz.box> (raw)
In-Reply-To: <CAC5n7TGSZEJUZL8ifj9-Bp5rzf1jCnuJKhwf2AdHQnKJ1GRw3A@mail.gmail.com> (Christopher Monsanto's message of "Mon, 1 Oct 2012 04:35:42 -0400")
On Mon, 1 Oct 2012 04:35:42 -0400 Christopher Monsanto <chris@monsan.to> wrote:
> The powerset is a set of sets. The empty set is always a member of the
> powerset, as the empty set is a subset of any other set. Or in other
> words, if (length (powerset ...)) is ever zero, you have a bug. Using
> '() or nil is incorrect.
Of course you're right, and in fact I don't use nil, but (list nil) (as
the iterative version I gave entails), which is here the same as '(). I
don't know why I wrote that I use nil, brain fart I guess.
Steve Berman
next prev parent reply other threads:[~2012-10-01 9:07 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-28 6:40 Modified keypad keys Per Starbäck
2012-09-28 8:23 ` Stefan Monnier
2012-09-28 15:29 ` Juri Linkov
2012-09-28 20:16 ` Stefan Monnier
2012-09-29 2:14 ` Stefan Monnier
2012-09-29 19:19 ` Juri Linkov
2012-09-30 1:41 ` Stefan Monnier
2012-09-30 9:56 ` Juri Linkov
2012-09-30 19:45 ` Stefan Monnier
2012-10-01 9:29 ` Juri Linkov
2012-10-01 15:03 ` Stefan Monnier
2012-10-04 18:41 ` Juri Linkov
2012-10-04 23:26 ` Andreas Schwab
2012-10-05 14:41 ` Andreas Schwab
2012-10-05 16:43 ` Juri Linkov
2012-10-05 16:55 ` Andreas Schwab
2012-10-05 17:05 ` Juri Linkov
2012-10-01 8:02 ` power set (Re: Modified keypad keys) Stephen Berman
2012-10-01 8:35 ` Christopher Monsanto
2012-10-01 9:07 ` Stephen Berman [this message]
2012-10-01 12:42 ` Lars Magne Ingebrigtsen
2012-10-01 13:06 ` Stephen Berman
2012-10-01 9:27 ` Juri Linkov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://www.gnu.org/software/emacs/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87haqeef1t.fsf@rosalinde.fritz.box \
--to=stephen.berman@gmx.net \
--cc=chris@monsan.to \
--cc=emacs-devel@gnu.org \
--cc=juri@jurta.org \
--cc=monnier@iro.umontreal.ca \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.savannah.gnu.org/cgit/emacs.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).