Re: ISSUE-4: Versioning, namespace URIs and MIME types

On Feb 18, 2009, at 1:42 PM, Larry Masinter wrote:

> I wrote:
>
>> The need for multiple libraries comes from having incompatible
>> languages or language versions. Incompatible languages and
>> language versions should be avoided--- however, not providing
>> a way of detecting which of several incompatible languages
>> or language versions was intended is a head-in-the-sand way
>> of pretending like they don't exist, and makes the problem
>> worse, not better.
>
> To which Dan responded:
>> I don't think so; the summary of this issue
>> http://www.w3.org/html/wg/tracker/issues/4
>> shows that there are some eyes-open arguments
>> that lead to the conclusion that we should not
>> provide a way of detective which of several
>> incompatible languages was intended:
>> * L. David Baron "Version information" -
>> http://lists.w3.org/Archives/Public/public-html/2007Apr/0279.html
>
> But that argument is
>
>> If we add version information, it will be tempting for the
>> implementation that Web authors are most commonly "writing for" to
>> use the version information to keep improvements in standards
>> compliance from applying to existing pages on the Web (i.e., pages
>> marked as older versions).
>
>
> The temptation to "break the web" in the name of Browser Wars
> exists whether or not the HTML specification provides a
> documented versioning mechanism, and an argument of the form
> "if we don't let them declare a version, then browsers that
> only support one version won't exist" I think deserves being
> called "head in the sand": not that those proposing the strategy
> haven't thought about it, but rather that somehow a browser
> vendor would be so influenced by not seeing a standard
> versioning mechanism as to keep them from introducing a
> non-standard version mechanism (such as what we've already
> seen with the various 'quirks' modes.)

You have to keep in mind the context for David's email: Microsoft was  
asking for a version attribute precisely so they could use it to  
trigger an unbounded number of future quirks modes. This wasn't a  
hypothetical fear, rather, it was a response to exactly what was  
requested and proposed.

Since then, IE8 introduced a nonstandard versioning mechanism, but PR  
considerations (and/or principled adherence to standards and  
interoperability, you be the judge) led them to limit this and make  
best-effort support for the latest standards the default.

So I think experience since David's original email bears him out. It  
does seem to make a difference whether or not the spec has an official  
versioning hook. It doesn't prevent versioning mechanisms for bug  
compatibility from being created, but it does limit their  
effectiveness in producing anti-competitive side effects.

Regards,
Maciej

Received on Wednesday, 18 February 2009 22:08:53 UTC