W3C home > Mailing lists > Public > public-webapps@w3.org > January to March 2009

Re: [Widgets] Widget Gallery RSS like sharing format

From: Andrew Welch <andrew.j.welch@gmail.com>
Date: Wed, 18 Mar 2009 08:35:17 +0000
Message-ID: <74a894af0903180135n1ad78801o2a9e9032ff4c2b8c@mail.gmail.com>
To: Robin Berjon <robin@berjon.com>
Cc: marcosc@opera.com, Thomas Landspurg <thomas.landspurg@gmail.com>, SUZANNE Benoit RD-SIRP-ISS <benoit.suzanne@orange-ftgroup.com>, public-webapps@w3.org
2009/3/17 Robin Berjon <robin@berjon.com>:
> On Mar 17, 2009, at 13:24 , Marcos Caceres wrote:
>>
>> Agreed. Thinking forward, how do you recommend we identify version 2.0
>> of the widget configuration file format (or should we just cross that
>> bridge when we get to it?) ?
>
> Personally, I would recommend that we don't :) Version identifiers are
> largely useless and experience shows that users use them wrong (e.g. a bunch
> of SVG out there that's labelled as 1.1 is really 1.2, but people just
> copy-paste the root element).
>
> There are strategies to implement versioning of XML vocabularies which don't
> require having a version identifier. These are generally based on an
> "ignore" approach whereby elements and attributes that the processor doesn't
> know about are silently skipped. That means we can add new features in the
> next revision and it won't break older UAs. If at some point we make
> breaking changes, then we just change the namespace.
>
> Note that this needs to be defined in v1, so no, I think we have to cross
> that bridge now. SVG includes this strategy:
>
>  http://www.w3.org/TR/SVGMobile12/implnote.html#UnsupportedProps
>
> It is worth pointing out that porting the same strategy to the configuration
> document would be simpler.

Are you sure changing the namespace is preferable to a version
attribute?  Seems very drastic, and usually it's best to avoid doing
it as it makes all tools that process existing markup redundant.

Also, you mention most users "just copy-paste the root element" -
surely you'd still have the problem if you change the namespace?

At the moment, I don't think there is any establised "right way" when
versioning xml, but changing the namespace is a bad idea.


-- 
Andrew Welch
http://andrewjwelch.com
Kernow: http://kernowforsaxon.sf.net/
Received on Wednesday, 18 March 2009 08:35:52 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 18:49:30 GMT