Re: [Json] "best practices" Vs. Profile for i-json

Tim Bray <tbray@textuality.com> Mon, 04 August 2014 20:24 UTC

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From: Tim Bray <tbray@textuality.com>
Date: Mon, 04 Aug 2014 13:24:19 -0700
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To: John Cowan <cowan@mercury.ccil.org>
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Cc: IETF JSON WG <json@ietf.org>, Nico Williams <nico@cryptonector.com>, Stephen Dolan <stephen.dolan@cl.cam.ac.uk>, Larry Masinter <masinter@adobe.com>
Subject: Re: [Json] "best practices" Vs. Profile for i-json
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How is this different/better than what
http://tools.ietf.org/html/draft-ietf-json-i-json-02#section-2.2 currently
says?  I don’t actually disagree with this formulation, but I think that in
practical terms it’s pretty well isomorphic to the current language.


On Mon, Aug 4, 2014 at 10:47 AM, John Cowan <cowan@mercury.ccil.org> wrote:

> Nico Williams scripsit:
>
> > Is a MUST really needed?  Suppose you have an encoder that produces
> > numbers (not irrationals) that require better-than-IEEE754 to represent
> > exactly.  A parser that can only handle IEEE754 should accept such
> > numbers, but with loss of precision/range -- exactly what we already
> > knew to expect from JSON as far as interoperability goes.
>
> A fair point.  We can use the verbal formula employed by Unicode for
> normalization, something like this:
>
>    A sending implementation [MUST NOT/SHOULD NOT] expect a receiving
>    implementation to distinguish between two numeric literals whose
>    decimal values round to the same IEEE754 double-precision value
>    (using standard round-to-nearest, ties-to-even rounding).
>
> How's that?
>
> --
> John Cowan          http://www.ccil.org/~cowan        cowan@ccil.org
> A few times, I did some exuberant stomping about, like a hippo auditioning
> for Riverdance, though I stopped when I thought I heard something at
> the far side of the room falling over in rhythm with my feet.  --Joseph
> Zitt
>
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