Re: TWO Change proposals for ISSUE-41 : Distributed Extensibility

On Mar 17, 2010, at 12:36 AM, Leif Halvard Silli wrote:

> Maciej Stachowiak, Tue, 16 Mar 2010 18:23:29 -0700:
>> Hi Rob,
>>
>> Thanks for your submissions. I have recorded both of your Change
>> Proposals on the issue status page:
>> http://dev.w3.org/html5/status/issue-status.html#ISSUE-041
>>
>> I have left the call for volunteers open, in case anyone else chooses
>> to submit any additional proposals.
>
> I have created another proposal, with Rob's proposal as starting  
> point:
>
> http://www.w3.org/html/wg/wiki/ChangeProposals/html:xmlns

Thank you for your submission. Now recorded at: http://dev.w3.org/html5/status/issue-status.html#ISSUE-041

>
> Short description:
>
> * real namespace *prefixes* with some restrictions:
>  - for elements, then XMLNS declared prefixes are permitted on
> <script> (see what AmpleSDK does) and in foreign namespaces and inside
> attributes (e.g. RDFa)
>  - for attributes of HTML elements, then it is permitted with a
> specific underscore syntax: _prefix:attribute=""
> * every prefix must be linked to a spec with a namespace URI
>  - however, it is not always necessary to use prefix and XMLNS in the
> code;
>  - the alternative is to use it in null namespace, see below.
> * possible to register a default namespace URI for a prefix:
>  - _name="" then has the prefix _name:, without the actual use of the
> prefix or of xmlns:_name=*.
>  - this permits _vendorname="value" attributes, without use of xmlns
> or prefix in the code
>  - this also allows _publicname="value" attribute, both with and
> without xmlns or prefix (registrant decides)
>  - the namespace allows _publicname="" to be reused inside XML
> documents (via the namespace).
>  - if UA(s) doesn't support the default namespace URI of _name=", then
> _publicname="" as well as _vendorname="" is in null namespaces.
> * possible to reuse attributes from other namespaces:
>  - <div _svg:attribute="value">
>  - both xmlns and _prefix must then be used.
>  - of course, in user agent is without namespace support, then e.g.
> _svg:attribute would count as a single attribute in null namespace.
> * purpose of the underscore syntax is to signal "extension" and to
> avoid clashes with existing namespaces as well as to avoid that  
> authors
> uses it for elements.
>
> I would describe my proposal as different from Rob's in that it puts
> more weight on the namespace URI. The intention with my proposal is to
> allow real namespaces in text/html. To allow real namespaces, there
> must be severe restrictions on the use and interpretation of them.  Or
> else, if existing "talisman" namespaces became "enabled", then pages
> would fall apart ... (Jotspot namespace of Google, Microsoft office
> namespaces etc.) The choice of the underscore "prefix" also avoids  
> that
> authors use the syntax to create namespaced elements inside text/html.
> (An element beginning with underscore is not treated as an element in
> text/html.)
> -- 
> Leif Halvard Silli
>

Received on Wednesday, 24 March 2010 08:03:56 UTC