From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.help Subject: Re: Emacs Lisp coding style question Date: Wed, 02 Jul 2014 09:50:50 -0400 Message-ID: References: <87mwcrudf5.fsf@kuiper.lan.informatimago.com> <87k37vykb2.fsf@gmail.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1404309117 26428 80.91.229.3 (2 Jul 2014 13:51:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 2 Jul 2014 13:51:57 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Wed Jul 02 15:51:52 2014 Return-path: Envelope-to: geh-help-gnu-emacs@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 1X2Kwv-00058r-EI for geh-help-gnu-emacs@m.gmane.org; Wed, 02 Jul 2014 15:51:49 +0200 Original-Received: from localhost ([::1]:53219 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2Kwv-0003Wa-4U for geh-help-gnu-emacs@m.gmane.org; Wed, 02 Jul 2014 09:51:49 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:56242) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2Kwc-0003WM-5g for help-gnu-emacs@gnu.org; Wed, 02 Jul 2014 09:51:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X2KwP-0002Tj-Tv for help-gnu-emacs@gnu.org; Wed, 02 Jul 2014 09:51:30 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:58613) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X2KwP-0002TY-ND for help-gnu-emacs@gnu.org; Wed, 02 Jul 2014 09:51:17 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1X2KwK-0004eT-CE for help-gnu-emacs@gnu.org; Wed, 02 Jul 2014 15:51:12 +0200 Original-Received: from 75-119-224-253.dsl.teksavvy.com ([75.119.224.253]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 02 Jul 2014 15:51:12 +0200 Original-Received: from monnier by 75-119-224-253.dsl.teksavvy.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 02 Jul 2014 15:51:12 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 31 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 75-119-224-253.dsl.teksavvy.com User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4.50 (gnu/linux) Cancel-Lock: sha1:NQ1WYVD6FxQUElUguGCvLOC6smU= X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:98506 Archived-At: >>> But (without being able to give concrete examples right now) I noticed >>> that advanced Lispers tend to call this 'C-style', consider the let I've never seen it referred to as "C-style". To me "C-style" would be (let (a b c d e) (setq a (foo-a)) (setq b (foo-b)) ...) >>> What would be the recommended style for Emacs Lisp, or is this just a >>> matter of taste? Mostly taste, and it depends on the specifics. I.e. it depends on whether the intermediate names can be useful as code documentation, and indentation issues may also tip the balance between the two. >> Notice that both code might compile to the exact same binary, so there's >> no efficiency advantage in either. The Emacs Lisp implementation (both interpreted and compiled) is not sophisticated enough to get the same efficiency out of the let-binding version, actually. > But in terms of uncompiled user-code - would the impact of the let > bindings here be worth thinking about performance? No the difference should not be noticeable anyway. Stefan