From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: Emacs rewrite in a maintainable language Date: Sun, 18 Oct 2015 19:11:13 +0200 Message-ID: <87k2qkm79q.fsf@fencepost.gnu.org> References: <561A19AB.5060001@cumego.com> <87k2qrki45.fsf@wanadoo.es> <8737xf9je9.fsf@fencepost.gnu.org> <87pp0fm0j3.fsf@gnu.org> <87r3kusx8z.fsf@fencepost.gnu.org> <83lhb26eb9.fsf@gnu.org> <876126key3.fsf@gnu.org> <83fv1a6bfu.fsf@gnu.org> <87d1weo7u9.fsf@gnu.org> <83zizi3qr0.fsf@gnu.org> <87lhb1n81y.fsf@gnu.org> <83si594wt3.fsf@gnu.org> <87io64iigs.fsf@gnu.org> <87r3kso1gr.fsf@fencepost.gnu.org> <87wpuks5ek.fsf@T420.taylan> <83vba4i1z3.fsf@gnu.org> <87pp0cqgjf.fsf@T420.taylan> <83twpoi0sp.fsf@gnu.org> <878u70qf75.fsf@T420.taylan> 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 1445188589 17397 80.91.229.3 (18 Oct 2015 17:16:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 18 Oct 2015 17:16:29 +0000 (UTC) Cc: Eli Zaretskii , ludo@gnu.org, emacs-devel@gnu.org To: taylanbayirli@gmail.com (Taylan Ulrich =?utf-8?Q?=22Bay=C4=B1rl=C4=B1?= =?utf-8?Q?=2FKammer=22?=) Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Oct 18 19:16:28 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 1ZnrZJ-0007tu-Da for ged-emacs-devel@m.gmane.org; Sun, 18 Oct 2015 19:16:25 +0200 Original-Received: from localhost ([::1]:34825 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrZJ-00007H-0J for ged-emacs-devel@m.gmane.org; Sun, 18 Oct 2015 13:16:25 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:45252) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrUl-0001e7-1s for emacs-devel@gnu.org; Sun, 18 Oct 2015 13:11:43 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZnrUk-00037A-Bt for emacs-devel@gnu.org; Sun, 18 Oct 2015 13:11:42 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:49738) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrUg-000322-R0; Sun, 18 Oct 2015 13:11:38 -0400 Original-Received: from localhost ([127.0.0.1]:35322 helo=lola) by fencepost.gnu.org with esmtp (Exim 4.82) (envelope-from ) id 1ZnrUf-0005v0-FJ; Sun, 18 Oct 2015 13:11:37 -0400 Original-Received: by lola (Postfix, from userid 1000) id 3C3D4E0DB0; Sun, 18 Oct 2015 19:11:13 +0200 (CEST) In-Reply-To: <878u70qf75.fsf@T420.taylan> ("Taylan Ulrich =?utf-8?Q?=5C=22Bay=C4=B1rl=C4=B1=2FKammer=5C=22=22's?= message of "Sun, 18 Oct 2015 19:06:22 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2001:4830:134:3::e 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:191979 Archived-At: taylanbayirli@gmail.com (Taylan Ulrich "Bay=C4=B1rl=C4=B1/Kammer") writes: > (The other day I was hit by this issue while working on Guile's C code, > where I forgot that a scm_blahblah_p predicate will return SCM_FALSE > which is not 0 thus not false in C. Like Qnil in Emacs.) >From src/lisp.h: /* True, since Qnil's representation is zero. Every place in the code that assumes Qnil is zero should verify (NIL_IS_ZERO), to make it easy to find such assumptions later if we change Qnil to be nonzero. */ enum { NIL_IS_ZERO =3D XLI_BUILTIN_LISPSYM (iQnil) =3D=3D 0 }; --=20 David Kastrup