Re: Custom Elements: 'data-' attributes

On Mon, 12 May 2014 11:00:20 +0200, Anne van Kesteren <annevk@annevk.nl>  
wrote:

> On Fri, May 9, 2014 at 12:56 PM, Ryosuke Niwa <rniwa@apple.com> wrote:
>> On the other hand, if the same element had exposed contentEditable  
>> property, then UA's native contentEditable property would simply be  
>> overridden since it would appear higher up in the prototype chain.   
>> It's true that this custom element's contentEditable would have  
>> completely different semantics from that on other elements but that  
>> wouldn't break websites that use this custom element as long as authors  
>> are only accessing contentEditable property on instances of the custom  
>> element for semantics C.
>
> I forgot the exact details, but we had some amount of trouble when we
> introduced min and max attributes due to sites using expandos with the
> same names.
>
> I think we need something better than encouraging certain conventions
> if we want this to work.

Bare names in event handler content attributes are troublesome.

For instance, sites doing:

<button onclick="action()">

made us have to rename <button action> to <button formaction> (the new  
.action reflecting action="" was closer in the scope chain than the  
intended function).

Global attributes have the same issue.

So when we research if it's safe to add a new global attribute, it's not  
enough to measure how often such an attribute is used in the wild. We need  
to research bare names in event handlers also.

-- 
Simon Pieters
Opera Software

Received on Monday, 12 May 2014 09:24:47 UTC