Re: [webcomponents] Inheritance in Custom Elements (Was Proposal for Cross Origin Use Case and Declarative Syntax)

On Thu, Dec 5, 2013 at 7:55 PM, Ryosuke Niwa <> wrote:

> On Nov 11, 2013, at 4:12 PM, Dimitri Glazkov <>
> wrote:
> > 3) The approach pollutes global name space with constructors. This had
> been voiced many times as unacceptable by developers.
> >
> > 4) How does build a custom element that uses <name-card> as its base
> element? What about <div> or any other HTML element?
> >
> > The last one remains to be the hardest. The tortured inheritance support
> is what killed <element> in the first place. We can't ignore the
> inheritance, since it is clearly present, in both DOM and JS. If we attempt
> to punt on supporting it, our decisions cut off the opportunities to evolve
> this right in the future, and will likely leave us with boogers like
> multiple syntaxes for inheritance vs. non-inheritance use cases.
> What exactly are you referring to by inheritance support?

> Inheritance from all builtin elements (e.g. subclasses of HTMLElement)?
> Or inheritance from custom elements authors have defined?

Sure, both are fine. Why should we treat them differently?

> And could you give us a pointer for a list of concrete use cases?

Look at any mature Web framework. They all have hierarchies of objects:!/api

The latter is undergoing a complete rewrite to be custom element-based, so
you might find it useful to study:

If the atomic unit of your framework is a DOM element, then DOM elements
must support being extended via inheritance. Jan Miksovsky (cc'd) is a good
person to talk about inheritance properties of custom elements.


Received on Friday, 6 December 2013 04:31:03 UTC