From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Andy Moreton Newsgroups: gmane.emacs.devel Subject: Re: Making 'eq' == 'eql' in bignum branch Date: Mon, 20 Aug 2018 17:58:00 +0100 Message-ID: References: <29f933ac-a6bf-8742-66a7-0a9d6d3e5a88@disroot.org> <87lgaio7xd.fsf@tromey.com> <877em1cb0i.fsf@tromey.com> <765767b2-d2e5-a9a6-f724-d58ecf4847bb@cs.ucla.edu> <76081b5d-8c10-0a37-2c97-d4864c0faa80@cs.ucla.edu> <09153aed-361d-4f82-d9ac-b502314769ae@cs.ucla.edu> <861sato21d.fsf@gmail.com> <8cfbbb98-ff52-dc9c-3660-f36ab43008a4@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1534784172 26733 195.159.176.226 (20 Aug 2018 16:56:12 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 20 Aug 2018 16:56:12 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1.50 (windows-nt) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Aug 20 18:56:08 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 1frnTM-0006sL-Im for ged-emacs-devel@m.gmane.org; Mon, 20 Aug 2018 18:56:08 +0200 Original-Received: from localhost ([::1]:48207 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1frnVT-0007ff-5X for ged-emacs-devel@m.gmane.org; Mon, 20 Aug 2018 12:58:19 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:44374) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1frnVN-0007fM-Ab for emacs-devel@gnu.org; Mon, 20 Aug 2018 12:58:13 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1frnVK-0006lM-5O for emacs-devel@gnu.org; Mon, 20 Aug 2018 12:58:13 -0400 Original-Received: from [195.159.176.226] (port=53501 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1frnVJ-0006ke-Ur for emacs-devel@gnu.org; Mon, 20 Aug 2018 12:58:10 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1frnTB-0006eU-7E for emacs-devel@gnu.org; Mon, 20 Aug 2018 18:55:57 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 24 Original-X-Complaints-To: usenet@blaine.gmane.org Cancel-Lock: sha1:Xm1r9odaTOdqnwgdcBrIuCYnYs8= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 195.159.176.226 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:228746 Archived-At: On Mon 20 Aug 2018, Paul Eggert wrote: > Andy Moreton wrote: >> The current codebase assumes that lisp bignum objects only exist for >> values outside fixnum range. Without fixnump how can tests check that >> values within fixnum range actually have a fixnum representation > > Tests cannot possibly check that, because 'fixnump' itself might simply return > t for any integer in fixnum range, even if the integer is internally > represented as a bignum. Only true if the tests can make no assumptions about the implementation. As the tests and the codebase are developed together that need not be the case. > Besides, the current codebase is not actually assuming that Lisp bignum > objects exist only for values outside fixnum range (the current codebase is > not assuming that bignums exist at all, for that matter). The C code most certainly does assume this. The lisp code does not care about representation (other than tripping over various bignum bugs that need fixing). AndyM