Re: Distributed Extensibility

On Aug 4, 2007, at 5:29 AM, Henri Sivonen wrote:

> OK. So do I understand correctly that the proposal is essentially  
> to extend the text/html serialization to a more general-purpose  
> (even if not fully general) alternative infoset serialization for  
> private systems where the people working with the private system  
> cannot be trusted to use XML?

I don't think there's any problem with trusting people to use XML.  
The more serious problem is that we cannot yet trust UAs to consume  
XML. If we could, then we would already have a decent HTML solution  
for namesapces (i.e., use XHTML).

>
>> Note: I don't care for the use of pejorative terms like walled  
>> gardens here.  I will readily concede that the term is accurate,  
>> but it is a distraction.
>
> Let's call them specific non-Web-scale systems then. The intent of  
> my question is was to understand what you were designing you  
> proposal for.
>
> Is it for
>  * Cases where the producer targets a specific consumer system and  
> known what its capabilities are and the specifiers of the consuming  
> system know that they can communicate specific requirements to the  
> producer and they use Web specs as the foundation of their private  
> stuff?
>  * Cases where the producer puts stuff out there on the Web where  
> various parties and pieces of software (including browsers) consume  
> it in ways that don't involve a specific relationship with the  
> producer?
>  * Both?

I too do not understand what is being proposed. Perhaps I'm trying to  
jump to eh conclusion too quickly, Let me try some questions (either  
answering will help or saying they'r off-base will send me back to  
the thread to try again):

Regarding your proposal:
• is it about adding some kind of namespace support to HTML?
• is it to add well-known namespaces or any arbitrary namespace?
• does it use the XML namespace declaration approach (mapping a URI  
to a prefix)?
• does it just use prefixes scoped locally to a document (with well- 
known ones reserved)?
• is it related to the handling of namespaces in IE?
• is it related to the handling of namespaces in Opera?
• is it related to the handling of namespaces in Firefox (like its  
hard-wired support for @role)?
• how does the discussion of CDATA sections relate?

>
>> While we should encourage extensions,
>
> This is not a technical objection to your proposal but I don't  
> think it is clear that *encouraging* extensions is a good idea in  
> the Web-scale case. We should encourage people to use well-known-- 
> not home-grown--markup vocabularies is cases that don't involve a  
> private bilateral agreement.

We already encourage extensions in the Web-scale case with the @class  
attribute and the @class attribute registry. In my view, namespaces  
are a more elegant extension mechanism than @class attributes. If we  
had wide-spread namesapce support, we would probably not need the  
microsyntax approaches that have sprung up (consider the hcard versus  
the XML/RDF vcard schema). Especially with the extension of CSS into  
most areas of browser presentation (like the bidi property and  
display: table, etc), it is more and more possible to express private  
semantics and present them in publicly consumable ways. Add to that  
behavioral schema reuse such as XLink or Xinclude and a XML private  
schema creator could piece together most of HTML out of thin air  
(though luckily they don't have to).

Take care,
Rob

Received on Saturday, 4 August 2007 14:43:57 UTC