From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: e and pi Date: Fri, 17 Sep 2010 10:15:50 +0200 Organization: Organization?!? Message-ID: <87lj70dbux.fsf@lola.goethe.zz> References: <8739t9xpt2.fsf@stupidchicken.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1284711369 22844 80.91.229.12 (17 Sep 2010 08:16:09 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 17 Sep 2010 08:16:09 +0000 (UTC) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Sep 17 10:16:08 2010 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 4.69) (envelope-from ) id 1OwW76-0004BV-7A for ged-emacs-devel@m.gmane.org; Fri, 17 Sep 2010 10:16:08 +0200 Original-Received: from localhost ([127.0.0.1]:47244 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OwW75-0003SI-Hv for ged-emacs-devel@m.gmane.org; Fri, 17 Sep 2010 04:16:07 -0400 Original-Received: from [140.186.70.92] (port=35550 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OwW6y-0003Pz-Dn for emacs-devel@gnu.org; Fri, 17 Sep 2010 04:16:01 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OwW6x-0004Yl-4d for emacs-devel@gnu.org; Fri, 17 Sep 2010 04:16:00 -0400 Original-Received: from lo.gmane.org ([80.91.229.12]:44803) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OwW6w-0004YX-VU for emacs-devel@gnu.org; Fri, 17 Sep 2010 04:15:59 -0400 Original-Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1OwW6v-00048O-V6 for emacs-devel@gnu.org; Fri, 17 Sep 2010 10:15:57 +0200 Original-Received: from p508edd3f.dip.t-dialin.net ([80.142.221.63]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 17 Sep 2010 10:15:57 +0200 Original-Received: from dak by p508edd3f.dip.t-dialin.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 17 Sep 2010 10:15:57 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 27 Original-X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: p508edd3f.dip.t-dialin.net X-Face: 2FEFf>]>q>2iw=B6, xrUubRI>pR&Ml9=ao@P@i)L:\urd*t9M~y1^:+Y]'C0~{mAl`oQuAl \!3KEIp?*w`|bL5qr,H)LFO6Q=qx~iH4DN; i"; /yuIsqbLLCh/!U#X[S~(5eZ41to5f%E@'ELIi$t^ Vc\LWP@J5p^rst0+('>Er0=^1{]M9!p?&:\z]|;&=NP3AhB!B_bi^]Pfkw User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) Cancel-Lock: sha1:MigLlLEBSLNgI/bivq9bPWhB1Eo= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) 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:130290 Archived-At: Simon Leinen writes: > On Fri, Sep 17, 2010 at 00:54, Chong Yidong wrote: >> What is the problem with dynamically scoping `e' and `pi'? > > Once programmers get used to lexical binding, they will reasonably > assume that they can use variable names such as "e" in a LET or in a > function/lambda parameter list without affecting outside code. > Letting such likely-to-be-used names be dynamically scoped violates > this assumption. Let's try to keep the number of these pitfalls as > low as possible. So what's wrong with letting defconst _not_ introduce dynamic scoping, and using it on e and pi? > Maybe we cannot expect to get rid of "t" and "nil", I have yet to see any code that reassigns t and nil, dynamically scoped or not. > but making "e" and "pi" available for lexical binding is a worthy > goal. Using defconst on them would appear to do that. -- David Kastrup