Re: [Json] Limitations on number size?

Nico Williams <nico@cryptonector.com> Tue, 04 June 2013 18:44 UTC

Return-Path: <nico@cryptonector.com>
X-Original-To: json@ietfa.amsl.com
Delivered-To: json@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 78FD521F9A8B for <json@ietfa.amsl.com>; Tue, 4 Jun 2013 11:44:29 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.833
X-Spam-Level:
X-Spam-Status: No, score=-1.833 tagged_above=-999 required=5 tests=[AWL=0.144, BAYES_00=-2.599, FM_FORGED_GMAIL=0.622]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VtfOqpI2YdGi for <json@ietfa.amsl.com>; Tue, 4 Jun 2013 11:44:23 -0700 (PDT)
Received: from homiemail-a70.g.dreamhost.com (caiajhbdcagg.dreamhost.com [208.97.132.66]) by ietfa.amsl.com (Postfix) with ESMTP id 6B30B21F99AE for <json@ietf.org>; Tue, 4 Jun 2013 11:41:23 -0700 (PDT)
Received: from homiemail-a70.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a70.g.dreamhost.com (Postfix) with ESMTP id 2690976812D for <json@ietf.org>; Tue, 4 Jun 2013 11:41:20 -0700 (PDT)
Received: from mail-we0-f178.google.com (mail-we0-f178.google.com [74.125.82.178]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: nico@cryptonector.com) by homiemail-a70.g.dreamhost.com (Postfix) with ESMTPSA id 8DFD8768109 for <json@ietf.org>; Tue, 4 Jun 2013 11:05:20 -0700 (PDT)
Received: by mail-we0-f178.google.com with SMTP id u53so516830wes.9 for <json@ietf.org>; Tue, 04 Jun 2013 11:05:18 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=Dn0d4+4lGXmhpu85o22jRSKpDe7RgDYwPwgelpN7O20=; b=gjQtH/u69AW0jS9lqwR5saOrXkTjoNgQnlqw0o34MqQyeKJkAy3FLCTF33vz2d+VJd xDCTGLUt+WZR2I8K+eMlXgqSb8hRCIlAeIizD0tabzSQKfBvaFSaUq223sjtmyXaVmDU obXkmpcUt+Z5Yz5IPlTVYWLZMd4fHy5atvOKzULHRFawNCZCSuI447HLpsngiKjNMYkq ZDbFI4Kmfmka3qV+8G7AEfLyHr1crbqOSlVm/Uy/zs+M4lC7p3UIHITs0yGtm7jM3KQZ 9Qlr5DaW38yJL+LwFukigFRe1Q48NWnUQw2fVkg8b+lOyBzPV4glAYwfToVoJeB4BwC+ T83g==
MIME-Version: 1.0
X-Received: by 10.194.77.66 with SMTP id q2mr25045701wjw.34.1370369118219; Tue, 04 Jun 2013 11:05:18 -0700 (PDT)
Received: by 10.216.63.136 with HTTP; Tue, 4 Jun 2013 11:05:18 -0700 (PDT)
In-Reply-To: <C30B2D0D-75A7-49A5-A190-5AD5DC1FCDCC@vpnc.org>
References: <CAK3OfOgPGi4PKxKAGEG=PCv-xaszMqWpUUUH2B9f0UaeMMO1gQ@mail.gmail.com> <C42654A3-E218-45A8-B368-4A60CB89619D@vpnc.org> <C4D8E604-E4F8-408B-B7DD-97226300C212@tzi.org> <CAK3OfOjDp=S=HZ5LTP3L+rqq1VjhSShakmBOJD9aPiN8fSULKw@mail.gmail.com> <C30B2D0D-75A7-49A5-A190-5AD5DC1FCDCC@vpnc.org>
Date: Tue, 4 Jun 2013 13:05:18 -0500
Message-ID: <CAK3OfOi6uNcXLCcStg90j2LqqdyVWQeoBAd0Mad-EjFEDyixpw@mail.gmail.com>
From: Nico Williams <nico@cryptonector.com>
To: Paul Hoffman <paul.hoffman@vpnc.org>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Cc: "json@ietf.org" <json@ietf.org>
Subject: Re: [Json] Limitations on number size?
X-BeenThere: json@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "JavaScript Object Notation \(JSON\) WG mailing list" <json.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/json>, <mailto:json-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/json>
List-Post: <mailto:json@ietf.org>
List-Help: <mailto:json-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/json>, <mailto:json-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 04 Jun 2013 18:44:29 -0000

On Tue, Jun 4, 2013 at 9:07 AM, Paul Hoffman <paul.hoffman@vpnc.org> wrote:
> And this is the point where one of the chairs says "please suggest specific wording changes to RFC 4627". (FWIW, Doug just got the XML for the bis draft yesterday, and we'll probably have the -00 soon, but that should not delay people making specific suggestions for wording changes.)

I think we need at least a note on interoperability, stating that
ECMAScript can only handle IEEE 754 64-bit numbers, other applications
might handle only 64-bit two's complement, others might handle bignum
integers, and yet others might handle arbitrary size reals.

Applications have to agree a priori on some schema (out of scope), and
this is part of that.

Should there be any advice to decoder implementors as to how to handle
numbers they cannot natively represent?

Nico
--