From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: Re: Why is booleanp defined this way? Date: Sat, 18 Apr 2015 03:06:02 +0200 Organization: Aioe.org NNTP Server Message-ID: <871tjint39.fsf@debian.uxu> References: <87siby7au6.fsf@mbork.pl> <877ftapd6v.fsf@debian.uxu> <87oammmfn4.fsf@kuiper.lan.informatimago.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1429319121 7349 80.91.229.3 (18 Apr 2015 01:05:21 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 18 Apr 2015 01:05:21 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Sat Apr 18 03:05:20 2015 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 1YjHCB-0003jn-Hn for geh-help-gnu-emacs@m.gmane.org; Sat, 18 Apr 2015 03:05:19 +0200 Original-Received: from localhost ([::1]:44151 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YjHCA-0000Bw-V2 for geh-help-gnu-emacs@m.gmane.org; Fri, 17 Apr 2015 21:05:18 -0400 Original-Path: usenet.stanford.edu!news.kjsl.com!feeder.erje.net!1.eu.feeder.erje.net!news2.arglkargh.de!news.mixmin.net!aioe.org!.POSTED!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 44 Original-NNTP-Posting-Host: feB02bRejf23rfBm51Mt7Q.user.speranza.aioe.org Original-X-Complaints-To: abuse@aioe.org User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux) X-Notice: Filtered by postfilter v. 0.8.2 Cancel-Lock: sha1:F1GxeCCOa08fZ4f1MwoioHHPFrw= Mail-Copies-To: never Original-Xref: usenet.stanford.edu gnu.emacs.help:211509 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:103791 Archived-At: "Pascal J. Bourguignon" writes: > You may want to compare: > > (defun normalize-boolean (obj) > (if obj t)) > (disassemble (byte-compile 'normalize-boolean)) > byte code: > args: (obj) > 0 varref obj > 1 goto-if-nil-else-pop 1 > 4 constant t > 5:1 return > > with: > > (defun g (x) (not (not x))) > byte code: > args: (x) > 0 varref x > 1 not > 2 not > 3 return > > (disassemble (byte-compile 'f)) ... you mean 'g? Are you saying (not (not x)) generates more efficient byte-code? I hate to break it to you, but the Commodore 64 demo era is long gone :) >> So I think `booleanp' shouldn't be thought of as >> a normalizer but rather as a type predicate, much >> like them `stringp', `integerp', and so on. > > Of course. That's what the "p" in "booleanp" means! If that is "of course" then what are we talking about? -- underground experts united http://user.it.uu.se/~embe8573