From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Juanma Barranquero" Newsgroups: gmane.emacs.devel Subject: Re: A question about read syntax and compiled backreferences Date: Sun, 28 Jan 2007 00:35:41 +0100 Message-ID: References: <85ac04xhg3.fsf@lola.goethe.zz> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: sea.gmane.org 1169940963 16827 80.91.229.12 (27 Jan 2007 23:36:03 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sat, 27 Jan 2007 23:36:03 +0000 (UTC) Cc: Andreas Schwab , Emacs Devel , Miles Bader To: "David Kastrup" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Jan 28 00:35:55 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1HAx5P-00013T-0T for ged-emacs-devel@m.gmane.org; Sun, 28 Jan 2007 00:35:55 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HAx5O-0002Gt-JI for ged-emacs-devel@m.gmane.org; Sat, 27 Jan 2007 18:35:54 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HAx5D-0002GV-Ue for emacs-devel@gnu.org; Sat, 27 Jan 2007 18:35:43 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HAx5C-0002GJ-Px for emacs-devel@gnu.org; Sat, 27 Jan 2007 18:35:43 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HAx5C-0002GG-LH for emacs-devel@gnu.org; Sat, 27 Jan 2007 18:35:42 -0500 Original-Received: from ug-out-1314.google.com ([66.249.92.170]) by monty-python.gnu.org with esmtp (Exim 4.52) id 1HAx5C-0007Yh-7L for emacs-devel@gnu.org; Sat, 27 Jan 2007 18:35:42 -0500 Original-Received: by ug-out-1314.google.com with SMTP id j3so1125226ugf for ; Sat, 27 Jan 2007 15:35:41 -0800 (PST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=G6/uduI3F4SFdJCmeI7XwOIc/GN9YyHPT0T8Mdl3CpRN9KGo6NQym8niZBFNXcKpIu9jtO8DkHl5Tfn1UsctOMMuYbSaKejg6utnvjmcDGXN7On1IT12V3jMSbiBeas0Mcq4hjG2vhKgdi7z7xged27jCqTGCocitEFeuq8TshI= Original-Received: by 10.67.96.14 with SMTP id y14mr6483158ugl.1169940941339; Sat, 27 Jan 2007 15:35:41 -0800 (PST) Original-Received: by 10.67.105.7 with HTTP; Sat, 27 Jan 2007 15:35:41 -0800 (PST) In-Reply-To: <85ac04xhg3.fsf@lola.goethe.zz> Content-Disposition: inline X-detected-kernel: Linux 2.4-2.6 (Google crawlbot) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:65545 Archived-At: On 1/27/07, David Kastrup wrote: > I don't think that > the ability to byte-compile code with circular lists is really > important enough to warrant this sort of inconvenience. I don't think having a local variable to deactivate it is inconvenient; after all, there's only a few elisp packages in Emacs where the slowdown is significant. OTOH, perhaps we could to the reverse: default print-circle to nil during byte-compilation, and add a variable to activate it for the few files that really need it. But anyway, some sensible behavior should be used: either we do compile correctly, or we detect circular lists (I mean, we detect uses of backreferences, like #1=...) and refuse to byte-compile it. What is not reasonable is byte-compiling it and generating wrong byte-code that can not be loaded. /L/e/k/t/u