[whatwg] classList should perhaps move from HTMLElement to Element

[Erik Dahlstrom]

On Thu, 03 May 2012 02:31:40 +0200, Cameron McCormack <cam at mcc.id.au>  
wrote:

> Rik Cabanier:
>> There was a discussion in the SVG WG about dropping the
>> SVGAnimatedxxx objects and have replace them with regular values. We
>> would need some tricks so we can change the DOM, but make it
>> backward compatible at the same time.
>
> We have discussed this a few times, and I would desparately love for it
> to work, but I am unconvinced it will.  I can an imagine an author
> writing code like:
>
>    if (!elt.className) ...
>
> to test if a class has been set.  Even if we made the
> SVGElement.className SVGAnimatedString object one that stringifies to
> the class, add a [PutForwards] on to it so that assigning a string
> works, it would still break the above code, since the ! operator always
> returns false for an object.

I don't think the use of animated 'class' attributes in svg is all that  
common, and I'd favor an approach that'd makes .className in svg a bit  
more like the html .className, perhaps in the way Cameron is suggesting.

On the topic of which interface the .classList property should be in,  
Element seems better than HTMLElement.

-- 
Erik Dahlstrom, Core Technology Developer, Opera Software
Co-Chair, W3C SVG Working Group
Personal blog: http://my.opera.com/macdev_ed