From: David Kastrup <dak@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Lexical binding and macros.
Date: Wed, 15 Dec 2010 17:16:40 +0100 [thread overview]
Message-ID: <87vd2v8107.fsf@lola.goethe.zz> (raw)
In-Reply-To: jwvipyv11zk.fsf-monnier+gnu.emacs.help@gnu.org
Stefan Monnier <monnier@iro.umontreal.ca> writes:
>> Do they still leak memory? From http://c2.com/cgi/wiki?EmacsLisp :
>
>> "Note that variables bound with lexical-let are never released, even
>> if they are never used. Try
>
>> (loop for i from 1 to 100000 collect (lexical-let ((x i)) '()))
>
>> and watch it eat memory. So making infinity (ZeroOneInfinity) lexical
>> variables is out of the question except for very small values of
>> infinity."
>
> Additionally to what Pascal already explained, I'll add that,
> lexical-let, like `loop' are relatively heavy macros, so you definitely
> don't want to run them interpreted (where the macro is re-expanded each
> time).
Why would they be reexpanded each time? They are macros. Their
expansion is done once and merely evalled each time.
Or do I misunderstand something here?
--
David Kastrup
next prev parent reply other threads:[~2010-12-15 16:16 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <mailman.40.1292017369.4804.help-gnu-emacs@gnu.org>
2010-12-12 4:10 ` Lexical binding and macros Barry Margolin
2010-12-12 17:14 ` LanX
2010-12-12 17:23 ` Pascal J. Bourguignon
2010-12-15 4:24 ` Stefan Monnier
2010-12-15 9:15 ` Elena
2010-12-15 12:38 ` Pascal J. Bourguignon
2010-12-15 15:40 ` Stefan Monnier
2010-12-15 16:16 ` David Kastrup [this message]
2010-12-15 17:37 ` Pascal J. Bourguignon
2010-12-15 17:54 ` Elena
2010-12-16 21:59 ` Stefan Monnier
2010-12-10 21:42 Alin Soare
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