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Re: Working Group Decision on ISSUE-120 rdfa-prefixes

From: James Graham <jgraham@opera.com>
Date: Tue, 29 Mar 2011 17:15:00 +0200
Message-ID: <4D91F774.1070401@opera.com>
To: Sam Ruby <rubys@intertwingly.net>
CC: HTML WG <public-html@w3.org>
On 03/29/2011 04:59 PM, Sam Ruby wrote:
> Running examples from the OpenGraph Protocol site through the
> facebook linter shows that removing the prefix declaration has no
> effect but changing it prevents any properties from being recognised.
> Code inspection of some of the other tools indicates that there are
> clients in Python, PHP, Ruby and Java that depend on literal matching
> of the string "og:".
> No change proposal was put forward suggesting that all usages be
> migrated to fixed prefixes. Nor was there any evidence put forward
> that fixes to these tools would break content.

I believe that is actually mentioned in the adopted change proposal:

"It is correct to say that the usage of the Facebook terms also reveal 
problems around namespaces insofar as many sites do not follow the 
advise of Facebook and do not add the right namespaces"

So it is clear that for backward-compatible processing of actual 
OpenGraph content one must not use prefixes but must treat the name as 
opaque. (I mention as an aside that this also implies that one cannot 
use the og: prefix in some other context since it may cause the data to 
be misappropriated as OpenGraph data).

> The fact that these
> tools have bugs is uncontested but that, in itself, does not help
> identify the proposal that draws the weakest objections.

Did you consider my further point that widespread failure to implement 
the prefix mechanism in client software provides clear evidence that the 
prefix mechanism is too complex for some constituency, either authors or 
Received on Tuesday, 29 March 2011 15:15:41 UTC

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