From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Michael Heerdegen Newsgroups: gmane.emacs.bugs Subject: bug#28254: 26.0.50; SRFI-2 and-let* Date: Sun, 03 Sep 2017 19:48:13 +0200 Message-ID: <87vakzwu5e.fsf@drachen> References: <87a82kdb4e.fsf@holos> <87inh36sap.fsf@users.sourceforge.net> <20170902021043.GA7509@holos.localdomain> <878thx7qcc.fsf@users.sourceforge.net> <20170902041424.GA21189@holos.localdomain> <87tw0lzn7w.fsf@drachen> <20170902133604.GA27251@holos.localdomain> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1504460977 23323 195.159.176.226 (3 Sep 2017 17:49:37 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 3 Sep 2017 17:49:37 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.0.50 (gnu/linux) Cc: Mark Oteiza , 28254@debbugs.gnu.org To: Noam Postavsky Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Sep 03 19:49:23 2017 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1doZ1C-0004il-DF for geb-bug-gnu-emacs@m.gmane.org; Sun, 03 Sep 2017 19:49:10 +0200 Original-Received: from localhost ([::1]:36639 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1doZ1J-0001Aj-DA for geb-bug-gnu-emacs@m.gmane.org; Sun, 03 Sep 2017 13:49:17 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:56094) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1doZ19-0001A3-JE for bug-gnu-emacs@gnu.org; Sun, 03 Sep 2017 13:49:12 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1doZ14-0006h7-MQ for bug-gnu-emacs@gnu.org; Sun, 03 Sep 2017 13:49:07 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:38064) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1doZ14-0006gx-IM for bug-gnu-emacs@gnu.org; Sun, 03 Sep 2017 13:49:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1doZ14-0002yo-8g for bug-gnu-emacs@gnu.org; Sun, 03 Sep 2017 13:49:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Michael Heerdegen Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 03 Sep 2017 17:49:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 28254 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 28254-submit@debbugs.gnu.org id=B28254.150446091411419 (code B ref 28254); Sun, 03 Sep 2017 17:49:02 +0000 Original-Received: (at 28254) by debbugs.gnu.org; 3 Sep 2017 17:48:34 +0000 Original-Received: from localhost ([127.0.0.1]:46745 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1doZ0c-0002y7-6G for submit@debbugs.gnu.org; Sun, 03 Sep 2017 13:48:34 -0400 Original-Received: from mout.web.de ([212.227.15.14]:52396) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1doZ0a-0002xv-Pv for 28254@debbugs.gnu.org; Sun, 03 Sep 2017 13:48:33 -0400 Original-Received: from drachen.dragon ([88.66.71.141]) by smtp.web.de (mrweb002 [213.165.67.108]) with ESMTPSA (Nemesis) id 0Mare6-1e4SEN2Rf0-00KPUt; Sun, 03 Sep 2017 19:48:17 +0200 In-Reply-To: (Noam Postavsky's message of "Sat, 2 Sep 2017 14:41:03 -0400") X-Provags-ID: V03:K0:H+EBLuyUylDK/WPyjMrhxwfBAi6qEe1ScECCzoA8vnzkdBp+Asu AMC/rm1IFnkcUxkvBchlipx3K56LwCqa1QyQyoIQBIOwQXh4dNl8WHZywt5FUQMkmGfK3Y7 1AM2aVCsPXG9gboYybaNTwDJCoMyzMWGpJjOQbW5bg/Lknd/WfkiHzY9t48ZdZWlPbq8GAF QFGejrVfkxqd6IEWh9m7Q== X-UI-Out-Filterresults: notjunk:1;V01:K0:uxNF/jFKhTY=:aHbDUqpjGVoBgT/M5D688/ 1Rgxc5SuzI60A46fUBbnia/WPVYYSrWmZVC022qh1v3BzEHO01sfSMCPLR9R9m3FMvQ8ue+Si pV1LkrhdiH0/krBj94oZyHAhkfwo/C00b7u5YvSzR8sm4VPwCrPZxjClybUbukzthm2Dm+Afz EkIcgeI8CYcEJQrjYg/JMI9c34fHYI9JX4pWMtHwTdn0NmsdQJD2xADr6wmI2m4eKsp9B1Og8 6LXLPMDR+49UF9YgZykirkOhdMJVYKc250LB3l4ysg0kYNmSLf8BPjmNcW2guOxIABqIqmnGX G5S5m9AARqmeeRo+IzrOh+FF3Q99foe4yt2qN6BzLI5eaA0YySUv7IUbsaHp0MpiKBs4bo23P GusSkp8GjDrUMMmvAp+7XXlg6WRA05Yilk1iG2pmml80/ssgFI6zZAFeO9fVITxy4VknDmJWN 5LHyOxeGxFNsniHcOf8Mv/odtfyqH1r6inpajwonUq90k7IHY/VVyJNRqpcGADiTvthtBQSAa a2OY7JHpocvIDCsB1vANTliVCWYfJY1gF6ZV9HTcRo017VAeQEssdlQZJzSGYoymW82ai0D50 lfxshjspSWQXDylGRb1wRpWCLEEzxuI1kjQIpZbUyVRWO2RU07Lf6T0kqAf8hSsgAw7fTN/lo q8UwF+pZ/7HiIuX7rD51vrMHiUf1nKS3UPVlJ8WnZVPH0H6G9Mg/+YWsY/e3jDnPnUxmKbiDU 1q9dplBZVkys/3ApsJLi6pCTmD4TaN/gSEbpjYiK12md4UU0mxbtbMnwTF+py0DzNKE8SwEu X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:136552 Archived-At: Noam Postavsky writes: > On Sat, Sep 2, 2017 at 9:36 AM, Mark Oteiza wrote: > > On 02/09/17 at 07:25am, Michael Heerdegen wrote: > >> > >> Isn't there a problem with EXPR being a symbol S, which already has a > >> different meaning (bind S to nil)? Though, this seems barely > >> useful to > >> me. Anyway, introducing (EXPR) would thus be backward incompatible. > > What would be the point of binding S to nil? In the foo-let macros > that would be equivalent to just putting nil (if non-list EXPRs are > supported), no? Eh hmm - yes, I think so. It isn't useful. > I think I'd be okay with dropping support for the S = (S nil) thing in > foo-let macros, so that all of the above would give (void-variable x). > Although perhaps the incompatibility with plain let would be annoying? > To be honest I hardly ever make use of S = (S nil) in plain let either > so it wouldn't hit me at all. I think the main use case is to declare a local variable when you don't care about the init value. In the case of if-let, S = (S nil) is not useful, since you can't use that binding neither in the "then" clause (because it won't be executed) nor in the "else" clauses (which ignore all bindings). Even if an `if-let' form is the result of a macro expansion, the S = (S nil) case isn't of any value. So I see no reasons to not drop support for it. Michael.