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Re: [Cbor] dCBOR moving from numerically-typeless systems

Carsten Bormann <cabo@tzi.org> Sun, 12 March 2023 20:47 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Sun, 12 Mar 2023 21:47:08 +0100
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To: Wolf McNally <wolf@wolfmcnally.com>
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Subject: Re: [Cbor] dCBOR moving from numerically-typeless systems
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On 2023-03-12, at 21:34, Wolf McNally <wolf@wolfmcnally.com> wrote:
> 
> semantically `null` expresses the absence of a value

This is the “big assumption” that I’m not convinced of.

This can get way more complicated, even with 0xf7 “undefined” being around as well.

Exhibit 1:

https://github.com/svaarala/cbor-specs/blob/master/cbor-absent-tag.rst

But, yes, in CBOR we can always invent more values to express various forms of not-being-there, being-mostly-absent, keeping-a-position-occupied-but-not-taken, …
(Harder to do in JSON.)  We even have NaN :-)

Grüße, Carsten

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