Re: [Json] JSON Schema Language: int53

Carsten Bormann <cabo@tzi.org> Fri, 23 August 2019 08:59 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 23 Aug 2019 10:59:13 +0200
Cc: "Manger, James" <James.H.Manger@team.telstra.com>, JSON WG <json@ietf.org>
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To: Ulysse Carion <ulysse@segment.com>
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Subject: Re: [Json] JSON Schema Language: int53
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On Aug 22, 2019, at 23:54, Ulysse Carion <ulysse@segment.com> wrote:
> 
> int53

Oh, it’s int54, because the separate sign bit gives you one more bit.

  (uint53 / nint53) => int54

(I’m ignoring the fact here that nint53 and thus int54 has one more position at the low end than I-JSON provides unambiguously.
But -2**53 == MININT54 can be represented in Javascript-limited JSON, with the only slightly annoying aspect being that you don’t really know whether it represents -2**53 or -2**53-1.)

Grüße, Carsten