Re: [Json] Limitations on number size?

Nico Williams <nico@cryptonector.com> Tue, 04 June 2013 09:03 UTC

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Date: Tue, 4 Jun 2013 02:59:29 -0500
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From: Nico Williams <nico@cryptonector.com>
To: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Json] Limitations on number size?
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On Tuesday, June 4, 2013, Carsten Bormann wrote:

> >>> JavaScript might not, but JSON actually does have indefinite length
> bignums. A JSON number can have any number of decimal digits.
> >>
> >> Yeah, but it is constrained to IEEE 754 64-bit floating point values,
> no?
> >
> > I don't see any limitation in RFC 4627, but it would be interesting if
> other folks here believe there is a limitation as Nico does.
>
> I think this is a nice example of the distinction between JSON the
> representation format, a specific JSON application, and JSON the ecosystem.
>
> JSON the format has no trouble in representing high-precision numbers (and
> big integers).
> So if somebody wanted to send ECDSA signature r/s values as JSON numbers,
> the format would be fine.


This is a plausible answer, sure.  I'm not sure I'd want to say JSON can
only represent IEEE754 64-bit numbers either, so if this is the consensus
then that'll be fine by me.

Do note that JSON's number encoding is indefinite-length...  ;)

Nico
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