Component Model

Here's a good starting point for learning about the component model spec, which is currently under development (also see periodically updating gh-pages).

Introduction

TODO Populate with beautifully crafted words.

• Component Model Use Cases
• Behavior Attachment

Overview

Isolation

Brainstorming page

Desugaring

From component model's perspective, all native form controls or elements with non-trivial behavior are also sub-classes of more primitive DOM elements with shadow DOM subtrees and behaviors attached. Thus, you can extend them and override shadow DOM subtrees just like you would with any component.

For example, in Rendering Form Controls with SVG use case, this allows the engineer to override appearance of a form element completely or to reuse it and supplement it with extra bits of appearance.

Styles

<style scoped> is a natural way to limit style sheets to only affect the shadow tree of a component. The component model follows the implementation suggested in this www-style thread. That is, a selector is only matched up to, and including, the scoping element - i.e., the parent element of <style scoped> - but not further. The exceptions are:

• the selector contains the :root pseudo-class (note that this will fail if not used within the first selector sequence), or
• the selector contains the :scope pseudo-class

CSS4: care must be taken that the subject of a selector is the scoping element or a descendant thereof.

[TODO: notes on crossing the boundary from/into the shadow tree]