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Re: [Cbor] Handling duplicate map keys

Laurence Lundblade <lgl@island-resort.com> Sat, 23 November 2019 17:11 UTC

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From: Laurence Lundblade <lgl@island-resort.com>
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Date: Sat, 23 Nov 2019 09:11:23 -0800
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Cc: Jeffrey Yasskin <jyasskin=40google.com@dmarc.ietf.org>, cbor@ietf.org
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Subject: Re: [Cbor] Handling duplicate map keys
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> On Nov 23, 2019, at 7:21 AM, Laurence Lundblade <lgl@island-resort.com> wrote:
> 
> To say it more in prose: They should either use a generic CBOR decoder that errors out on duplicates, or a CBOR decoder that passes duplicates up so the protocol implementation on top of CBOR can do the detection. What they must not do is use a decoder that does take first, take last or randomly takes one of the occurrences.

To be really explicit (for my brain too), it is never right for normal behavior of a CBOR protocol to rely on take first. It is *always* right to error out when duplicates are detected.

LL

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