From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: An idea: combine-change-calls Date: Mon, 26 Mar 2018 20:36:15 -0400 Message-ID: References: <20180324135024.GA6319@ACM> <20180325191424.GE6292@ACM> <20180326201728.GA28620@ACM> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1522110868 12480 195.159.176.226 (27 Mar 2018 00:34:28 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 27 Mar 2018 00:34:28 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Mar 27 02:34:24 2018 Return-path: Envelope-to: ged-emacs-devel@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 1f0cZE-0003AG-0a for ged-emacs-devel@m.gmane.org; Tue, 27 Mar 2018 02:34:24 +0200 Original-Received: from localhost ([::1]:59698 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0cbH-0005e9-7L for ged-emacs-devel@m.gmane.org; Mon, 26 Mar 2018 20:36:31 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55662) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0cbA-0005dr-HK for emacs-devel@gnu.org; Mon, 26 Mar 2018 20:36:25 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f0cb5-0007VF-Kf for emacs-devel@gnu.org; Mon, 26 Mar 2018 20:36:24 -0400 Original-Received: from pruche.dit.umontreal.ca ([132.204.246.22]:45756) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0cb5-0007Rv-Er for emacs-devel@gnu.org; Mon, 26 Mar 2018 20:36:19 -0400 Original-Received: from ceviche.home (lechon.iro.umontreal.ca [132.204.27.242]) by pruche.dit.umontreal.ca (8.14.7/8.14.1) with ESMTP id w2R0aGNq013822; Mon, 26 Mar 2018 20:36:16 -0400 Original-Received: by ceviche.home (Postfix, from userid 20848) id D471A66480; Mon, 26 Mar 2018 20:36:15 -0400 (EDT) In-Reply-To: <20180326201728.GA28620@ACM> (Alan Mackenzie's message of "Mon, 26 Mar 2018 20:17:28 +0000") X-NAI-Spam-Flag: NO X-NAI-Spam-Threshold: 5 X-NAI-Spam-Score: 0 X-NAI-Spam-Rules: 2 Rules triggered EDT_SA_DN_PASS=0, RV6250=0 X-NAI-Spam-Version: 2.3.0.9418 : core <6250> : inlines <6519> : streams <1782362> : uri <2615409> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 132.204.246.22 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:224083 Archived-At: > (defmacro combine-change-calls (beg end &rest form) > `(let* ((-beg- ,beg) > (-end- ,end) > (body (lambda () ,@form)) Don't use `let*` here since otherwise you have a variable capture if `form` uses variables with name -beg- or -end-, or if the expression `end` uses a variable named -beg-. [ and a nitpick: `form` is usually used for a single expression whereas here it holds a list of expressions, so I'd call it `forms`. ] Stefan