From unknown Sun Jul 27 03:21:37 2025 X-Loop: help-debbugs@gnu.org Subject: bug#30145: [PATCH] doc: Document undefined?. Resent-From: Arun Isaac Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Wed, 17 Jan 2018 17:53:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: report 30145 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch To: 30145@debbugs.gnu.org Cc: Arun Isaac X-Debbugs-Original-To: bug-guile@gnu.org Received: via spool by submit@debbugs.gnu.org id=B.15162115551614 (code B ref -1); Wed, 17 Jan 2018 17:53:02 +0000 Received: (at submit) by debbugs.gnu.org; 17 Jan 2018 17:52:35 +0000 Received: from localhost ([127.0.0.1]:60446 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ebrt5-0000Py-Ka for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:35 -0500 Received: from eggs.gnu.org ([208.118.235.92]:33505) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ebrt3-0000Pk-7z for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ebrsx-00089w-EB for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:28 -0500 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,T_DKIM_INVALID autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:50439) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ebrsx-00089q-Ba for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:27 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52700) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ebrsw-0001tX-9C for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ebrsr-0007yb-BQ for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:26 -0500 Received: from [2001:19f0:5:274f:4827:c39:448f:6777] (port=40916 helo=vultr.systemreboot.net) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ebrsq-0007sU-QI for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=systemreboot.net; s=default; h=Message-Id:Date:Subject:Cc:To:From:Sender: Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=of58HJdR4gP6juUcl0RZAnDTA0/6+ZeBbBjsKspuIBM=; b=XxMw6FjitwllEz1+jPPru66QiJ PUkVGc2k+0n/ZcsvzdEDN0ktMflcj+uLiIYnYfH0MzWzDXOWFvJ2aoIS2/cc9HhLcSiNLi1gLXvIj qSI9ZwBSo1FrWCIGvp+fYC4CPZYyo8KMs1DTqE9lIsxh4t/4+AenOPcSgeyBp/U6l3Fs=; Received: from [117.192.107.9] (helo=localhost.localdomain) by systemreboot.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90) (envelope-from ) id 1ebrsl-0006H4-D0; Wed, 17 Jan 2018 23:22:15 +0530 From: Arun Isaac Date: Wed, 17 Jan 2018 23:22:04 +0530 Message-Id: <20180117175204.1381-1-arunisaac@systemreboot.net> X-Mailer: git-send-email 2.15.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -4.1 (----) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -4.1 (----) * doc/ref/data-rep.texi: Document undefined?. --- doc/ref/data-rep.texi | 3 +++ 1 file changed, 3 insertions(+) diff --git a/doc/ref/data-rep.texi b/doc/ref/data-rep.texi index bb7f74afe..ed3a5a522 100644 --- a/doc/ref/data-rep.texi +++ b/doc/ref/data-rep.texi @@ -470,6 +470,9 @@ check to see if @var{x} is @code{SCM_UNBOUND}. History will not be kind to us. @end deftypefn +@deffn {Scheme Procedure} undefined? x +Return @code{#t} if @var{x} is undefined, else @code{#f}. +@end deffn @node Non-immediate objects @subsubsection Non-immediate objects -- 2.15.1 From unknown Sun Jul 27 03:21:37 2025 X-Loop: help-debbugs@gnu.org Subject: bug#30145: Acknowledgement ([PATCH] doc: Document undefined?.) Resent-From: Arun Isaac Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Thu, 18 Jan 2018 06:17:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 30145 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch To: 30145@debbugs.gnu.org Received: via spool by 30145-submit@debbugs.gnu.org id=B30145.151625619213044 (code B ref 30145); Thu, 18 Jan 2018 06:17:02 +0000 Received: (at 30145) by debbugs.gnu.org; 18 Jan 2018 06:16:32 +0000 Received: from localhost ([127.0.0.1]:60866 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ec3V1-0003OJ-Ng for submit@debbugs.gnu.org; Thu, 18 Jan 2018 01:16:31 -0500 Received: from vultr.systemreboot.net ([45.77.148.100]:60440) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ec3V0-0003O4-66 for 30145@debbugs.gnu.org; Thu, 18 Jan 2018 01:16:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=systemreboot.net; s=default; h=Content-Type:MIME-Version:Message-ID:Date: References:In-Reply-To:Subject:To:From:Sender:Reply-To:Cc: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=gh7B4GR2ogr1CM/3BkGMJx3jhLYUt0K1X4BYMCDeWEU=; b=dOUJckCpmuZ3/O2fPgi4KxArJ SgPp6UhsQxNBgdRdabsHOnYPTS23tcp22BJLJ3R2QLKkyAuu/CBss2xblokCx2cGJLEu7dno0seKg dwswyA1qY6Cn+H2csSoPIAJDX7ZiOFVcjG6qDtTT3K2AUF+tKRs7+OFnQpIFd2qNjI2+o=; Received: from [117.192.107.9] (helo=steel) by systemreboot.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90) (envelope-from ) id 1ec3Us-0008Uh-Cq for 30145@debbugs.gnu.org; Thu, 18 Jan 2018 11:46:22 +0530 From: Arun Isaac In-Reply-To: References: <20180117175204.1381-1-arunisaac@systemreboot.net> Date: Thu, 18 Jan 2018 11:46:20 +0530 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: -0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) I intended to document unspecified?. I have somehow gotten confused and ended up specifying it as undefined?. Disregard this patch. I will send a new one. From unknown Sun Jul 27 03:21:37 2025 X-Loop: help-debbugs@gnu.org Subject: bug#30145: [PATCH] doc: Document unspecified?. References: <20180117175204.1381-1-arunisaac@systemreboot.net> In-Reply-To: <20180117175204.1381-1-arunisaac@systemreboot.net> Resent-From: Arun Isaac Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Thu, 18 Jan 2018 06:21:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 30145 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch To: 30145@debbugs.gnu.org Cc: Arun Isaac Received: via spool by 30145-submit@debbugs.gnu.org id=B30145.151625645413525 (code B ref 30145); Thu, 18 Jan 2018 06:21:02 +0000 Received: (at 30145) by debbugs.gnu.org; 18 Jan 2018 06:20:54 +0000 Received: from localhost ([127.0.0.1]:60871 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ec3ZG-0003W5-At for submit@debbugs.gnu.org; Thu, 18 Jan 2018 01:20:54 -0500 Received: from vultr.systemreboot.net ([45.77.148.100]:60470) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ec3ZE-0003Vm-Cl for 30145@debbugs.gnu.org; Thu, 18 Jan 2018 01:20:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=systemreboot.net; s=default; h=Message-Id:Date:Subject:Cc:To:From:Sender: Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=UhvVmolPhsYf9cTCcIP/rzv+/4pA3wNhyUeWS0uWyLQ=; b=PT1eKNuk7VzKAX1MpV31ApIDux JdnYSTZMkfifihbt3XxMQAFmHV0NbQtnW3Q2HTO7wKrxfFa7gAnPOibmB+bwqoV65E7gXu0+ABCXZ RPfF+ZUgqR4O8jRi4Gys9EKJ5l+gCqcZafSR6F3Q2eir1D5N9ZcL0hRhoLN3ViMRFWak=; Received: from [117.192.107.9] (helo=localhost.localdomain) by systemreboot.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90) (envelope-from ) id 1ec3Z4-0000QQ-W5; Thu, 18 Jan 2018 11:50:43 +0530 From: Arun Isaac Date: Thu, 18 Jan 2018 11:50:29 +0530 Message-Id: <20180118062029.5655-1-arunisaac@systemreboot.net> X-Mailer: git-send-email 2.15.1 X-Spam-Score: -0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) * doc/ref/data-rep.texi: Document unspecified?. --- doc/ref/data-rep.texi | 3 +++ 1 file changed, 3 insertions(+) diff --git a/doc/ref/data-rep.texi b/doc/ref/data-rep.texi index bb7f74afe..f179a3560 100644 --- a/doc/ref/data-rep.texi +++ b/doc/ref/data-rep.texi @@ -470,6 +470,9 @@ check to see if @var{x} is @code{SCM_UNBOUND}. History will not be kind to us. @end deftypefn +@deffn {Scheme Procedure} unspecified? x +Return @code{#t} if @var{x} is unspecified, else @code{#f}. +@end deffn @node Non-immediate objects @subsubsection Non-immediate objects -- 2.15.1 From unknown Sun Jul 27 03:21:37 2025 X-Loop: help-debbugs@gnu.org Subject: bug#30145: [PATCH] doc: Document undefined?. Resent-From: Mark H Weaver Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Sun, 21 Jan 2018 14:37:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 30145 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch To: Arun Isaac Cc: 30145@debbugs.gnu.org Received: via spool by 30145-submit@debbugs.gnu.org id=B30145.151654537124298 (code B ref 30145); Sun, 21 Jan 2018 14:37:02 +0000 Received: (at 30145) by debbugs.gnu.org; 21 Jan 2018 14:36:11 +0000 Received: from localhost ([127.0.0.1]:36679 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edGjD-0006Jq-3C for submit@debbugs.gnu.org; Sun, 21 Jan 2018 09:36:11 -0500 Received: from world.peace.net ([50.252.239.5]:41504) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edGjB-0006Jb-TA for 30145@debbugs.gnu.org; Sun, 21 Jan 2018 09:36:10 -0500 Received: from [98.216.255.118] (helo=yeeloong) by world.peace.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1edGj5-0007VP-Lc; Sun, 21 Jan 2018 09:36:03 -0500 From: Mark H Weaver References: <20180117175204.1381-1-arunisaac@systemreboot.net> Date: Sun, 21 Jan 2018 09:33:40 -0500 In-Reply-To: <20180117175204.1381-1-arunisaac@systemreboot.net> (Arun Isaac's message of "Wed, 17 Jan 2018 23:22:04 +0530") Message-ID: <871sijnuwr.fsf@netris.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: 0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.0 (/) Arun Isaac writes: > * doc/ref/data-rep.texi: Document undefined?. Is 'undefined?' a procedure in your Guile? It's not available at my Guile REPL,and I can't find a single occurrence of 'undefined?' in my guile stable-2.2 git checkout. There is a special SCM_UNDEFINED value at the C level, but it's only used for a couple of internal purposes and not usable from Scheme at all. FYI, the two internal purposes are these: (1) if SCM_UNDEFINED is passed as an optional argument to a Scheme procedure implemented in C, this indicates that the optional argument was not actually present. (2) if SCM_UNDEFINED is stored in a top-level variable object, that indicates that the variable is no longer bound, i.e. it was actually removed. Mark From unknown Sun Jul 27 03:21:37 2025 X-Loop: help-debbugs@gnu.org Subject: bug#30145: [PATCH] doc: Document unspecified?. Resent-From: Mark H Weaver Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Sun, 21 Jan 2018 14:52:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 30145 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch To: Arun Isaac Cc: 30145@debbugs.gnu.org Received: via spool by 30145-submit@debbugs.gnu.org id=B30145.151654628525596 (code B ref 30145); Sun, 21 Jan 2018 14:52:01 +0000 Received: (at 30145) by debbugs.gnu.org; 21 Jan 2018 14:51:25 +0000 Received: from localhost ([127.0.0.1]:36699 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edGxx-0006em-3L for submit@debbugs.gnu.org; Sun, 21 Jan 2018 09:51:25 -0500 Received: from world.peace.net ([50.252.239.5]:41534) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edGxv-0006eZ-13 for 30145@debbugs.gnu.org; Sun, 21 Jan 2018 09:51:23 -0500 Received: from [98.216.255.118] (helo=yeeloong) by world.peace.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1edGxp-0007Zn-54; Sun, 21 Jan 2018 09:51:17 -0500 From: Mark H Weaver References: <20180117175204.1381-1-arunisaac@systemreboot.net> <20180118062029.5655-1-arunisaac@systemreboot.net> Date: Sun, 21 Jan 2018 09:48:54 -0500 In-Reply-To: <20180118062029.5655-1-arunisaac@systemreboot.net> (Arun Isaac's message of "Thu, 18 Jan 2018 11:50:29 +0530") Message-ID: <87wp0bmfmx.fsf@netris.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: 0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.0 (/) Hi Arun, Arun Isaac writes: > * doc/ref/data-rep.texi: Document unspecified?. > --- > doc/ref/data-rep.texi | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/doc/ref/data-rep.texi b/doc/ref/data-rep.texi > index bb7f74afe..f179a3560 100644 > --- a/doc/ref/data-rep.texi > +++ b/doc/ref/data-rep.texi > @@ -470,6 +470,9 @@ check to see if @var{x} is @code{SCM_UNBOUND}. History will not be kind > to us. > @end deftypefn > > +@deffn {Scheme Procedure} unspecified? x > +Return @code{#t} if @var{x} is unspecified, else @code{#f}. > +@end deffn I'm not sure it's a good idea to document this procedure as part of our public API, but if we were to document it, it would require a more informative description. It's nonsensical to ask whether a given object is "unspecified". When the Scheme standards say that the result of a computation is an unspecified value, that means that *any* Scheme object could be returned. In Guile, for historical reasons, we usually return a particular object SCM_UNSPECIFIED (a.k.a. *unspecified*) in cases where the specification says that the result is unspecified. However, we make no promises that this will remain the case in future versions of Guile. The number of legitimate uses for 'unspecified?' is extremely small. In fact, I can think of only one: when a REPL prints the result of a user's computation, it is nice to avoid printing "*unspecified*" and instead print nothing in that case. In almost every other case, use of 'unspecified?' implies an assumption that it's possible to detect when a value is an "unspecified" value, when in fact that is fundamentally impossible. What do you think? Mark From unknown Sun Jul 27 03:21:37 2025 MIME-Version: 1.0 X-Mailer: MIME-tools 5.505 (Entity 5.505) X-Loop: help-debbugs@gnu.org From: help-debbugs@gnu.org (GNU bug Tracking System) To: Arun Isaac Subject: bug#30145: closed (Re: bug#30145: [PATCH] doc: Document unspecified?.) Message-ID: References: <20180117175204.1381-1-arunisaac@systemreboot.net> X-Gnu-PR-Message: they-closed 30145 X-Gnu-PR-Package: guile X-Gnu-PR-Keywords: patch Reply-To: 30145@debbugs.gnu.org Date: Sun, 21 Jan 2018 18:23:02 +0000 Content-Type: multipart/mixed; boundary="----------=_1516558982-20090-1" This is a multi-part message in MIME format... ------------=_1516558982-20090-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Your bug report #30145: [PATCH] doc: Document undefined?. which was filed against the guile package, has been closed. The explanation is attached below, along with your original report. If you require more details, please reply to 30145@debbugs.gnu.org. --=20 30145: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=3D30145 GNU Bug Tracking System Contact help-debbugs@gnu.org with problems ------------=_1516558982-20090-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at 30145-done) by debbugs.gnu.org; 21 Jan 2018 18:22:27 +0000 Received: from localhost ([127.0.0.1]:37330 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edKGB-0005DE-Hw for submit@debbugs.gnu.org; Sun, 21 Jan 2018 13:22:27 -0500 Received: from vultr.systemreboot.net ([45.77.148.100]:34246) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1edKG8-0005Cy-G3 for 30145-done@debbugs.gnu.org; Sun, 21 Jan 2018 13:22:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=systemreboot.net; s=default; h=Content-Type:MIME-Version:Message-ID:Date: References:In-Reply-To:Subject:Cc:To:From:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=rmyKhiUkMbEB2r6emObvsrkt1VBLMxHIWb2fO1mjeW0=; b=m+Lg5/Qu0p3dd5UUJG3fujQx6 BjG2E2A5VtD0lmZ7U8a1Rzz919zGd9AiTwGLz4lOkvG34ll6Yyfx+OOKcgvGfdIR0zAmJFFavGUGi vh7KY8nZ4bNJiJYliRkEKodkkhUIMyAnQvpbDZBGLbsumBrd3mPuFMcKeoXYJgV9pAepk=; Received: from [103.61.74.183] (helo=steel) by systemreboot.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90) (envelope-from ) id 1edKFu-0006Ql-UL; Sun, 21 Jan 2018 23:52:10 +0530 From: Arun Isaac To: Mark H Weaver Subject: Re: bug#30145: [PATCH] doc: Document unspecified?. In-Reply-To: <87wp0bmfmx.fsf@netris.org> References: <20180117175204.1381-1-arunisaac@systemreboot.net> <20180118062029.5655-1-arunisaac@systemreboot.net> <87wp0bmfmx.fsf@netris.org> Date: Sun, 21 Jan 2018 23:52:08 +0530 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: -0.0 (/) X-Debbugs-Envelope-To: 30145-done Cc: 30145-done@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) Mark H Weaver writes: About undefined?: That was a typo. I mentioned that in a later message. > It's nonsensical to ask whether a given object is "unspecified". When > the Scheme standards say that the result of a computation is an > unspecified value, that means that *any* Scheme object could be > returned. > > In Guile, for historical reasons, we usually return a particular object > SCM_UNSPECIFIED (a.k.a. *unspecified*) in cases where the specification > says that the result is unspecified. However, we make no promises that > this will remain the case in future versions of Guile. > > The number of legitimate uses for 'unspecified?' is extremely small. In > fact, I can think of only one: when a REPL prints the result of a user's > computation, it is nice to avoid printing "*unspecified*" and instead > print nothing in that case. > > In almost every other case, use of 'unspecified?' implies an assumption > that it's possible to detect when a value is an "unspecified" value, > when in fact that is fundamentally impossible. > > What do you think? I agree. I didn't put very much thought into the matter before I sent the patch. I needed unspecified? for a patch to GNU Guix. I found the info documentation missing for unspecified? and thought I'll write it. Later, it turned out unspecified? was not necessary for the Guix patch after all. But, I had already documented unspecified?. So, I sent it here. Anyways, I'll close this bug report. ------------=_1516558982-20090-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at submit) by debbugs.gnu.org; 17 Jan 2018 17:52:35 +0000 Received: from localhost ([127.0.0.1]:60446 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ebrt5-0000Py-Ka for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:35 -0500 Received: from eggs.gnu.org ([208.118.235.92]:33505) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ebrt3-0000Pk-7z for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ebrsx-00089w-EB for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:28 -0500 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,T_DKIM_INVALID autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:50439) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ebrsx-00089q-Ba for submit@debbugs.gnu.org; Wed, 17 Jan 2018 12:52:27 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52700) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ebrsw-0001tX-9C for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ebrsr-0007yb-BQ for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:26 -0500 Received: from [2001:19f0:5:274f:4827:c39:448f:6777] (port=40916 helo=vultr.systemreboot.net) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ebrsq-0007sU-QI for bug-guile@gnu.org; Wed, 17 Jan 2018 12:52:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=systemreboot.net; s=default; h=Message-Id:Date:Subject:Cc:To:From:Sender: Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=of58HJdR4gP6juUcl0RZAnDTA0/6+ZeBbBjsKspuIBM=; b=XxMw6FjitwllEz1+jPPru66QiJ PUkVGc2k+0n/ZcsvzdEDN0ktMflcj+uLiIYnYfH0MzWzDXOWFvJ2aoIS2/cc9HhLcSiNLi1gLXvIj qSI9ZwBSo1FrWCIGvp+fYC4CPZYyo8KMs1DTqE9lIsxh4t/4+AenOPcSgeyBp/U6l3Fs=; Received: from [117.192.107.9] (helo=localhost.localdomain) by systemreboot.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90) (envelope-from ) id 1ebrsl-0006H4-D0; Wed, 17 Jan 2018 23:22:15 +0530 From: Arun Isaac To: bug-guile@gnu.org Subject: [PATCH] doc: Document undefined?. Date: Wed, 17 Jan 2018 23:22:04 +0530 Message-Id: <20180117175204.1381-1-arunisaac@systemreboot.net> X-Mailer: git-send-email 2.15.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -4.1 (----) X-Debbugs-Envelope-To: submit Cc: Arun Isaac X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -4.1 (----) * doc/ref/data-rep.texi: Document undefined?. --- doc/ref/data-rep.texi | 3 +++ 1 file changed, 3 insertions(+) diff --git a/doc/ref/data-rep.texi b/doc/ref/data-rep.texi index bb7f74afe..ed3a5a522 100644 --- a/doc/ref/data-rep.texi +++ b/doc/ref/data-rep.texi @@ -470,6 +470,9 @@ check to see if @var{x} is @code{SCM_UNBOUND}. History will not be kind to us. @end deftypefn +@deffn {Scheme Procedure} undefined? x +Return @code{#t} if @var{x} is undefined, else @code{#f}. +@end deffn @node Non-immediate objects @subsubsection Non-immediate objects -- 2.15.1 ------------=_1516558982-20090-1--