From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Helmut Eller Newsgroups: gmane.emacs.devel Subject: Re: Idempotency of add-hook wrt lambda expressions Date: Thu, 05 Mar 2009 17:33:16 +0100 Message-ID: References: <74F2CF19-2E71-473F-A352-A628B3B29A8E@gmail.com> <861vtcxpt1.fsf@lola.quinscape.zz> <20090305164532.GC1855@muc.de> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1236270868 8153 80.91.229.12 (5 Mar 2009 16:34:28 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 5 Mar 2009 16:34:28 +0000 (UTC) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Mar 05 17:35:45 2009 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 1LfGXm-0008L7-BX for ged-emacs-devel@m.gmane.org; Thu, 05 Mar 2009 17:35:34 +0100 Original-Received: from localhost ([127.0.0.1]:53658 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LfGWR-0001PP-0M for ged-emacs-devel@m.gmane.org; Thu, 05 Mar 2009 11:34:11 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LfGVm-00017b-Ir for emacs-devel@gnu.org; Thu, 05 Mar 2009 11:33:30 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LfGVk-00016K-At for emacs-devel@gnu.org; Thu, 05 Mar 2009 11:33:29 -0500 Original-Received: from [199.232.76.173] (port=60840 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LfGVk-00016D-4U for emacs-devel@gnu.org; Thu, 05 Mar 2009 11:33:28 -0500 Original-Received: from main.gmane.org ([80.91.229.2]:54060 helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LfGVj-00004s-NL for emacs-devel@gnu.org; Thu, 05 Mar 2009 11:33:27 -0500 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1LfGVg-0002qU-Ef for emacs-devel@gnu.org; Thu, 05 Mar 2009 16:33:24 +0000 Original-Received: from dialin-226013.rol.raiffeisen.net ([195.254.226.13]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 05 Mar 2009 16:33:24 +0000 Original-Received: from eller.helmut by dialin-226013.rol.raiffeisen.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 05 Mar 2009 16:33:24 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 23 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: dialin-226013.rol.raiffeisen.net User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.90 (gnu/linux) Cancel-Lock: sha1:tCJGt+RlgGD24gS5K0AKmhrEWmI= X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) 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:109474 Archived-At: * Alan Mackenzie [2009-03-05 17:45+0100] writes: > One of the reasons for using a lambda is to save having to think up a > function name, and to save cluttering up one's .emacs, or whatever. > Compare > > (add-hook 'foo-mode-hook (lambda (some-minor-mode 1))) > > with > > (defun switch-some-minor-mode-on () > (some-minor-mode 1)) > (add-hook 'foo-mode-hook 'switch-some-minor-mode-on) > I've seen this idiom in several places: (add-hook 'foo-mode-hook (defun switch-some-minor-mode-on () (some-minor-mode 1))) Helmut.