Re: [Json] What does "break compatibility" mean?

Nico Williams <nico@cryptonector.com> Thu, 28 February 2013 20:47 UTC

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Date: Thu, 28 Feb 2013 14:46:54 -0600
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From: Nico Williams <nico@cryptonector.com>
To: Tim Bray <tbray@textuality.com>
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Cc: Barry Leiba <barryleiba@computer.org>, Paul Hoffman <paul.hoffman@vpnc.org>, json@ietf.org
Subject: Re: [Json] What does "break compatibility" mean?
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On Thu, Feb 28, 2013 at 2:06 PM, Tim Bray <tbray@textuality.com> wrote:
> It’s clear to me that, *for the purposes of the IETF*, someone needs to say
> “People sending JSON MUST NOT use duplicate keys.”  The fact that certain
> libraries allow less-clueful developers to do this, and that parsing
> software is observed to behave unpredictably when they do, should only
> encourage us.

The obvious compromise is to say senders MUST NOT send dup object keys
and receivers MUST take the last key value pair of any dup keys,
per-ECMAScript.  The latter preserves compatibility.

Nico
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