Re: review of "The root element" subsection (considering html/@charset)

On Jul 10, 2007, at 1:02 PM, Dan Connolly wrote:

>
> On Tue, 2007-07-10 at 14:21 +0200, Simon Pieters wrote:
>> On Tue, 10 Jul 2007 12:43:44 +0200, Robert Burns  
>> <rob@robburns.com> wrote:
>>
>>>> No. It is not a requirement for UAs. The requirements for UAs are:
>>>>
>>>>    http://www.whatwg.org/specs/web-apps/current-work/#determining0
>>>
>>> I wasn't asking about the UA requirements, I was asking if there  
>>> was any
>>> research on the current behavior (that we're trying to be backwards
>>> compatible with).
>>
>> There was. It is documented in the section referenced above.
>>
>>     http://www.hixie.ch/tests/adhoc/html/parsing/encoding/
>>
>>>> Perhaps, but it isn't compatible with existing UAs.
>>
>>> Do we already have some tests on this?
>>
>> We do now... ;-)
>>
>>     http://simon.html5.org/test/html/parsing/encoding/001.htm
>
> Thanks... I noted those test materials in
>   http://esw.w3.org/topic/HtmlTestMaterials
>
> (I encourage others to do likewise with any test materials they have.)
>
> This compatibility form of argument is likely to come
> up often enough that it should have a home in our
> design principles.
>
> Trying out the current draft
> http://esw.w3.org/topic/HTML/ProposedDesignPrinciples ...
>
> I think this principle comes closest...
>
> "Degrade Gracefully
>
> New versions of HTML should allow documents using them to work in user
> agents that don't yet support it. Authors will be reluctant to use new
> features that cause problems in older browsers, or that don't provide
> some sort of graceful fallback."
>
> So even if we allowed <html charset='utf-8'>, authors would be
> reluctant to use it until it was widely supported.

I'm aware of the "degrade gracefully" principle. However, its not  
clear whether the @charset attribute  on <meta> degrades any more  
gracefully than a new @charset attribute on <html>. Perhaps those  
tests have been performed. I don't know. It would also be worth  
testing the robustness of BOM only encoding detection (for the BOM  
only detectable encodings).

So I'm not deliberately introducing proposals with poor degradation.  
Quite the opposite, I'm trying to consider that in any of the  
proposals I make. Its just not clear, without further testing, which  
proposals degrade most gracefully.

As for security, I think that's a very tricky issue. However, messing  
with and complicating encoding declarations at all raises risks. I'm  
just trying to find a way of doing it that's the least complicated  
for authors.  Its not that the current draft doesn't have the same  
potential security risks.

Take care,
Rob

Received on Tuesday, 10 July 2007 22:02:42 UTC