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Re: [Json] I-JSON Topic #5: Numbers

John Cowan <cowan@mercury.ccil.org> Tue, 29 April 2014 17:15 UTC

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Date: Tue, 29 Apr 2014 13:15:02 -0400
From: John Cowan <cowan@mercury.ccil.org>
To: Carsten Bormann <cabo@tzi.org>
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References: <535EB3BF.8080606@cisco.com> <CAHBU6ivjF9ULW0yGSVdJi2D6QgUThuhym_ZhpgLM=cvLu=mAiQ@mail.gmail.com> <CF841AAE.47D86%jhildebr@cisco.com> <CAO1wJ5RJL5jXYMRo9pxhNGc9Si5CLj5EmMLxWYntXsUFkGUbRA@mail.gmail.com> <56A5D291-62BC-4E3C-A734-F8BC2358E831@tzi.org>
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Subject: Re: [Json] I-JSON Topic #5: Numbers
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Carsten Bormann scripsit:

> Maybe what is meant here is excluding a number that doesn't round trip as a binary64?

That's what the MUST means.  The SHOULD means something different.

> Really, what needs to be excluded is the *intention* to obtain more
> precision! and there is no way to see whether there was such an
> intention from the actual JSON text.

No, there isn't, that's why the MUST is a constraint on emitters, and it is
precisely a constraint on what they expect rather than on what they do.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan@ccil.org
LEAR: Dost thou call me fool, boy?
FOOL: All thy other titles thou hast given away:
That thou wast born with.

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