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domenic / html-as-custom-elements

HTML as Custom Elements
https://domenic.github.io/html-as-custom-elements/
Apache License 2.0
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Some interfaces are shared by multiple tag names #19

Open arv opened 10 years ago

arv commented 10 years ago

blockquote and q both use HTMLQuoteElement.

Custom elements do not all a prototype to be reused for multiple tag names.

dglazkov commented 10 years ago

Also, constructor makes no sense in the context of these funky elements.

domenic commented 10 years ago

This seems like a bug in custom elements. Can we fix that? Or is there a reason for this restriction?

dglazkov commented 10 years ago

The idea was to treat this ambiguity as a bug in prior design: there should be a 1:1 relationship between a tag and an element constructor. But that was a while back, when we wanted to kill document.createElement and replace it with just constructors. If we no longer want this, we can definitely revisit this.

annevk commented 10 years ago

You could imagine HTMLQuoteElement allowing new HTMLQuoteElement("q") and HTMLQuoteElement("blockquote"). Seems brittle though if we later need an actual interface for <q> or some such (this has happened, element starts out as HTMLElement, needs its own class later).

domenic commented 10 years ago

Hmm. I think that HTML has good reasons for allowing multiple tag names to share the same class: different default styling; different semantics; different ARIA roles (#14). I am surprised custom elements do not allow such things.

On the other hand I can see the argument that it was a legacy mistake, and that today all new elements should have their own classes, even if those classes are just empty extensions of HTMLElement.

annevk commented 10 years ago

How are those good reasons for sharing the class?

domenic commented 10 years ago

Because none of them require their own API, and this you can get all those differences while still sharing a single API thar can be consulted, extended, and generically used.

annevk commented 10 years ago

What happens the moment you decide to add an attribute?

domenic commented 10 years ago

I don't understand the problem. The attribute gets added?

annevk commented 10 years ago

You have SharedElement for E and E'. Now you add an attribute to E which also requires a dedicated API. Now SharedElement can no longer be used for E. It will need to extend it. But the original constructor has no knowledge of this.