Re: ISSUE-274 (prohibited-semantics): Semantics of "prohibited" features [TTML2]

That's reasonable.


On Tue, Aug 20, 2013 at 3:11 AM, Michael Dolan <mdolan@newtbt.com> wrote:

> Although I personally would interpret the spec as requiring the
> processor’s semantic support for the initial value (as worded now or as
> proposed), I think it would be clearer to explicitly state this.****
>
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>                 Mike****
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> *From:* Glenn Adams [mailto:glenn@skynav.com]
> *Sent:* Monday, August 19, 2013 8:50 PM
> *To:* Timed Text Working Group
> *Subject:* Re: ISSUE-274 (prohibited-semantics): Semantics of
> "prohibited" features [TTML2]****
>
> ** **
>
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> On Mon, Aug 19, 2013 at 9:26 PM, Timed Text Working Group Issue Tracker <
> sysbot+tracker@w3.org> wrote:****
>
> ISSUE-274 (prohibited-semantics): Semantics of "prohibited" features
> [TTML2]
>
> http://www.w3.org/AudioVideo/TT/tracker/issues/274
>
> Raised by: Pierre-Anthony Lemieux
> On product: TTML2
>
> (Draft) TTML 2 states that "In addition, a feature or extension may be
> specified as prohibited, in which case it must not appear in or be used by
> a Document Instance, and, if it does appear, may result in the Document
> Instance being rejected or processing otherwise aborted."
>
> A feature such as #overflow states that "A TTML transformation processor
> supports the #overflow feature if it recognizes and is capable of
> transforming all defined values of the tts:overflow attribute."
>
> How does one specify that only the default value of tts:overflow shall be
> used, i.e. that a document instance shall not contain tts:overflow
> declarations but that the TTML processor shall use the default value of
> tts:overflow?****
>
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> I'll remove the "or be used by", which should fix your concern. When I
> wrote it, I was not including the processor use of a default non-specified
> value in "use".****
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