From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Andy Wingo Newsgroups: gmane.lisp.guile.bugs Subject: bug#26026: Defining a method named zero? breaks primitive zero? Date: Wed, 19 Apr 2017 17:12:12 +0200 Message-ID: <87mvbcl9df.fsf@igalia.com> References: NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1492614795 771 195.159.176.226 (19 Apr 2017 15:13:15 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 19 Apr 2017 15:13:15 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) Cc: 26026-done@debbugs.gnu.org To: Alejandro Sanchez Original-X-From: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Wed Apr 19 17:13:10 2017 Return-path: Envelope-to: guile-bugs@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 1d0rI4-0008RQ-OO for guile-bugs@m.gmane.org; Wed, 19 Apr 2017 17:13:09 +0200 Original-Received: from localhost ([::1]:48709 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d0rIA-0002KV-E5 for guile-bugs@m.gmane.org; Wed, 19 Apr 2017 11:13:14 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:46252) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d0rI2-0002KK-6e for bug-guile@gnu.org; Wed, 19 Apr 2017 11:13:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d0rHy-0007Tw-Vg for bug-guile@gnu.org; Wed, 19 Apr 2017 11:13:06 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:58853) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1d0rHy-0007TZ-Nq for bug-guile@gnu.org; Wed, 19 Apr 2017 11:13:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1d0rHy-0002lY-G6 for bug-guile@gnu.org; Wed, 19 Apr 2017 11:13:02 -0400 Resent-From: Andy Wingo Original-Sender: "Debbugs-submit" Resent-To: bug-guile@gnu.org Resent-Date: Wed, 19 Apr 2017 15:13:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: cc-closed 26026 X-GNU-PR-Package: guile X-GNU-PR-Keywords: Mail-Followup-To: 26026@debbugs.gnu.org, wingo@igalia.com, hiphish@openmailbox.org Original-Received: via spool by 26026-done@debbugs.gnu.org id=D26026.149261474410577 (code D ref 26026); Wed, 19 Apr 2017 15:13:02 +0000 Original-Received: (at 26026-done) by debbugs.gnu.org; 19 Apr 2017 15:12:24 +0000 Original-Received: from localhost ([127.0.0.1]:57050 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1d0rHM-0002kX-0Y for submit@debbugs.gnu.org; Wed, 19 Apr 2017 11:12:24 -0400 Original-Received: from pb-sasl1.pobox.com ([64.147.108.66]:50716 helo=sasl.smtp.pobox.com) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1d0rHK-0002kP-9S for 26026-done@debbugs.gnu.org; Wed, 19 Apr 2017 11:12:22 -0400 Original-Received: from sasl.smtp.pobox.com (unknown [127.0.0.1]) by pb-sasl1.pobox.com (Postfix) with ESMTP id 22D2381D34; Wed, 19 Apr 2017 11:12:20 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type:content-transfer-encoding; s=sasl; bh=aSNHcXs/Jy42 nyqcGHMOcvBDGJI=; b=Ivdk7hhSnqAF8xiBS3N2YhOBJ+O1g82seu9dWPWh7uxj UCTskJvv08zOVcP+STx3ySquDbkpXydhIVtHluE+90phIm007+6+JDdU8b90IyT7 DfkFDTmz1r7U9LWhTViwlZI1z1wuIftZwfCpbPZb8o64ylq1+YBihY8iJCU9Uy0= Original-Received: from pb-sasl1.nyi.icgroup.com (unknown [127.0.0.1]) by pb-sasl1.pobox.com (Postfix) with ESMTP id 1A44581D33; Wed, 19 Apr 2017 11:12:20 -0400 (EDT) Original-Received: from rusty (unknown [88.160.190.192]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by pb-sasl1.pobox.com (Postfix) with ESMTPSA id 3F07681D32; Wed, 19 Apr 2017 11:12:19 -0400 (EDT) In-Reply-To: (Alejandro Sanchez's message of "Wed, 8 Mar 2017 12:07:56 +0100") X-Pobox-Relay-ID: 94C7C554-2512-11E7-A9B1-07D2064AB293-02397024!pb-sasl1.pobox.com X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-guile@gnu.org List-Id: "Bug reports for GUILE, GNU's Ubiquitous Extension Language" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Original-Sender: "bug-guile" Xref: news.gmane.org gmane.lisp.guile.bugs:8755 Archived-At: On Wed 08 Mar 2017 12:07, Alejandro Sanchez write= s: > If I define a =E2=80=98zero?=E2=80=99 predicate method for a custom class= the primitive =E2=80=98zero?=E2=80=99 is lost. Here is a simple vector mod= ule: > > ;;; File vector2.scm > (define-module (vector2) > #:use-module (oop goops) > #:export ( get-x get-y zero?)) >=20=09 > (define-class () > (x #:init-value 0 #:getter get-x #:init-keyword #:x) > (y #:init-value 0 #:getter get-y #:init-keyword #:y) ) > > (define-generic zero?) > (define-method (zero? (v )) > (and (zero? (get-x v)) > (zero? (get-y v)))) > > In the Guile REPL try executing the following code: > > scheme@(guile-user)> (use-modules (oop goops) (vector2)) > scheme@(guile-user)> (zero? (make )) > > This will display=20 > > WARNING: (guile-user): `zero?' imported from both (ice-9 r5rs) and (vect= or2) > ERROR: In procedure scm-error: > ERROR: No applicable method for #< zero? (1)> in call (zero? 0) >=20=09 > Entering a new prompt. Type `,bt' for a backtrace or `,q' to continue. > scheme@(guile-user) [1]> ,bt > In vector2.scm: > 11:7 2 (_ #< 105e87e00>) > In oop/goops.scm: > 1438:4 1 (cache-miss 0) > In unknown file: > 0 (scm-error goops-error #f "No applicable method for ~S in c= all ~S" (#< =E2=80=A6) =E2=80=A6) > > Apparently the problem is that =E2=80=98zero?=E2=80=99 is defined in two = modules and > the vector2 definition overrides it. This isn=E2=80=99t the case with oth= er > primitives like =E2=80=98+=E2=80=99 or =E2=80=98*=E2=80=99, so this seems= like a bug? I had built > Guile from HEAD a few days ago, my package manager shows 6fff84d as > the version number, so I guess that must be the hash of the commit > HEAD was pointing to at that time. Actually the (vector2) module makes a fresh definition for zero?. You can tell because zero? is in its export list. So instead of extending the primitive-generic that is zero?, you are making a new definition. See: scheme@(guile-user)> (define-module (foo) #:export (zero?)) $1 =3D # scheme@(foo)> (zero? 0) :4:0: :4:0: Unbound variable: zero? Entering a new prompt. Type `,bt' for a backtrace or `,q' to continue. If you want to extend a primitive-generic, then do that by not exporting zero?. In a way it's like mutating the primitive in place, giving it additional powers. Andy