Re: [Cbor] correctness of implied top level array?

Joe Hildebrand <jhildebrand@mozilla.com> Thu, 28 February 2019 19:23 UTC

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From: Joe Hildebrand <jhildebrand@mozilla.com>
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Date: Thu, 28 Feb 2019 12:23:24 -0700
Cc: Carsten Bormann <cabo@tzi.org>, cbor@ietf.org, Laurence Lundblade <lgl@island-resort.com>
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To: Michael Richardson <mcr+ietf@sandelman.ca>
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Subject: Re: [Cbor] correctness of implied top level array?
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> On Feb 27, 2019, at 5:53 PM, Michael Richardson <mcr+ietf@sandelman.ca> wrote:
> 
> An alternative way to do the desired action (and bring this inside of cbor)
> would be an (indefinite?) array type that was specified to concatenate.
> 
> I'm not really arguing for this, but I think it's worth knowing why this
> would be less good a thing.

It's an interesting idea.  One of the reasons this didn't feel right to me was that my initial take on indefinite-length arrays was to read the whole array, growing memory as needed.  I've moved on from that, but would expect others to find themselves in a similar spot.

More interestingly though, there are times when I might want to use an optional external length-framing approach, like embedding a single CBOR data item in a WebSocket message.

— 
Joe Hildebrand