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From: Drew Adams <drew.adams@oracle.com>
To: Barry Margolin <barmar@alum.mit.edu>, help-gnu-emacs@gnu.org
Subject: RE: hash strangeness
Date: Mon, 3 Nov 2014 19:04:49 -0800 (PST)	[thread overview]
Message-ID: <0041d5f2-b328-4017-a748-ead21589f05e@default> (raw)
In-Reply-To: <<barmar-14233C.17480902112014@88-209-239-213.giganet.hu>>

> > I expect '(a b c) to create a new list with these symbols
> > every time it runs.
> 
> Why do you expect that?
> '(a b c) is short for (quote (a b c)). quote returns its argument, it
> doesn't make a copy of it.
> 
> I'm sure somewhere in the Elisp programming manual it mentions that you
> shouldn't use destructive functions on literal lists, like the Common
> Lisp spec does.

Here is one place: the Elisp manual, node `Rearrangement`.  Search for
"a common pitfall".

https://www.gnu.org/software/emacs/manual/html_node/elisp/Rearrangement.html



  parent reply	other threads:[~2014-11-04  3:04 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-02 11:20 hash strangeness Tom
2014-11-02 12:09 ` Tom
2014-11-02 18:20   ` Thien-Thi Nguyen
2014-11-02 20:45     ` Tom
     [not found]     ` <mailman.12618.1414961152.1147.help-gnu-emacs@gnu.org>
2014-11-02 22:25       ` Pascal J. Bourguignon
2014-11-02 22:48       ` Barry Margolin
2014-11-03 21:29         ` Tom
2014-11-04  1:57           ` Robert Thorpe
2014-11-04  2:16           ` Michael Heerdegen
     [not found]       ` <<barmar-14233C.17480902112014@88-209-239-213.giganet.hu>
2014-11-04  3:04         ` Drew Adams [this message]
2014-11-04  7:39           ` Marcin Borkowski
     [not found] <mailman.12577.1414927271.1147.help-gnu-emacs@gnu.org>
2014-11-02 18:43 ` Pascal J. Bourguignon
2014-11-02 20:48   ` Tom

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