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Re: [Cbor] Do we care about array-tags issue 6, clamped-uint8 arrays?

Carsten Bormann <cabo@tzi.org> Fri, 26 July 2019 02:06 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Thu, 25 Jul 2019 22:06:30 -0400
Cc: Sean Leonard <dev+ietf@seantek.com>, cbor@ietf.org
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To: Jeffrey Yasskin <jyasskin@google.com>
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Subject: Re: [Cbor] Do we care about array-tags issue 6, clamped-uint8 arrays?
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On Jul 25, 2019, at 16:36, Jeffrey Yasskin <jyasskin@google.com> wrote:
> 
> I remain
> uncomfortable with having a serialization format describe behaviors
> that the data had or should have when it was or is loaded into a
> program.

I don’t know how to avoid that.  If the input is an array, in most generic decoders I get an array to work from.  If the input is instead a map, I get a map (or a JavaScript object); that has quite different behavior.  So the supplier of the input already has a lot of control over the data structures that are input to my system.  Uint8ClampedArray just adds a slight twist to that as it might look too much like a Uint8Array.
None of this relieves an application of validating its input — with a standard serialization format and a robust generic decoder, this can now simply be done on a higher level.

Grüße, Carsten

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