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Re: Optional Extensions

From: Prasad Yendluri <pyendluri@webmethods.com>
Date: Tue, 27 Jan 2004 12:00:04 -0800
Message-ID: <4016C344.5040501@webmethods.com>
To: 'Web Services Description' <www-ws-desc@w3.org>

Sorry, the difficulty I have with the MUST ignore things *you don't 
understand* is that, tools can arbitrarily ignore 60 out of the 100 
hundred optional one (say) and no one will ever know which 40 got 
ignored. Yes a tool can still flag them but, by spec'ing a MUST ignore 
we just made that tool non-conformant to the spec, did we not?

Prasad

Yaron Goland wrote:

>As David explained, the issue is true backwards compatibility. If someone
>adds in a new feature that can be safely ignored by old processors they need
>to know that old processors will ignore the feature. Today the specification
>doesn't provide any clear guidance on what to do with optional unrecognized
>extensions. Ideally the spec would say 'the default behavior is to ignore
>the XML element and its children.' If a tool wishes to override that
>behavior, that's fine. But interoperability comes from having good defaults
>and that's what we need the spec to provide.
>
>BTW, let's keep in mind that if an extension is not safe to ignore then this
>is where wsdl:required comes in. We are only talking about extensions that
>the author of the WSDL had decided could be safely ignored without violating
>the author's intended meaning or usage of the WSDL.
>
>	Yaron
>
Received on Tuesday, 27 January 2004 15:00:10 GMT

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