From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: The purpose of makunbound Date: Thu, 19 Feb 2015 20:59:22 -0500 Message-ID: References: NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1424397606 24023 80.91.229.3 (20 Feb 2015 02:00:06 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 20 Feb 2015 02:00:06 +0000 (UTC) Cc: Richard Stallman , emacs-devel@gnu.org To: Kelly Dean Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Feb 20 02:59:57 2015 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1YOcsm-0002FR-0L for ged-emacs-devel@m.gmane.org; Fri, 20 Feb 2015 02:59:56 +0100 Original-Received: from localhost ([::1]:58814 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YOcsl-0007b1-9f for ged-emacs-devel@m.gmane.org; Thu, 19 Feb 2015 20:59:55 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:34873) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YOcsh-0007au-U5 for emacs-devel@gnu.org; Thu, 19 Feb 2015 20:59:52 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YOcse-0003wB-PD for emacs-devel@gnu.org; Thu, 19 Feb 2015 20:59:51 -0500 Original-Received: from ironport2-out.teksavvy.com ([206.248.154.181]:45350) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YOcse-0003vu-L4; Thu, 19 Feb 2015 20:59:48 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AkwUAPOG1lTO+LI//2dsb2JhbABbgwaDX0+FBMBlBAICgQ1EAQEBAQEBfIQNAQQBIzMjBQsLGgIYDgICFBgNJIg4CLgylXEBAQgCAR+BIY4kMweCaIFCBYonn0uBRSKCAhyBbiCCcwEBAQ X-IPAS-Result: AkwUAPOG1lTO+LI//2dsb2JhbABbgwaDX0+FBMBlBAICgQ1EAQEBAQEBfIQNAQQBIzMjBQsLGgIYDgICFBgNJIg4CLgylXEBAQgCAR+BIY4kMweCaIFCBYonn0uBRSKCAhyBbiCCcwEBAQ X-IronPort-AV: E=Sophos;i="5.09,536,1418101200"; d="scan'208";a="110965839" Original-Received: from 206-248-178-63.dsl.teksavvy.com (HELO pastel.home) ([206.248.178.63]) by ironport2-out.teksavvy.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 19 Feb 2015 20:59:46 -0500 Original-Received: by pastel.home (Postfix, from userid 20848) id 86CD51309; Thu, 19 Feb 2015 20:59:22 -0500 (EST) In-Reply-To: (Kelly Dean's message of "Thu, 19 Feb 2015 23:51:39 +0000") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 206.248.154.181 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:183312 Archived-At: > variables. Regardless of the interpretation, there are two different kinds > of =E2=80=9Funbind=E2=80=9D events: the one caused by exit of a =C2=ABlet= =C2=BB (which > unshadows/restores the outer/previous value), and the one caused by > makunbound (which sets the value to void). Ah, I think I understand a bit better. I think treating "void" as an event is the error: it's a state. OTOH, the "revert to previous state" done at the end of `let' is indeed an event. So one is an action and the other is a state. > or killing the buffer-local), yet the same terminology is used for both. I don't see "unbind" used anywhere in the description of what `let' does, nor is it a term that I've heard used (other than by yourself) to refer to what happens at the end of a "let". Stefan