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Clarify that declarative custom element definitions don't contain declarative shadow roots. #1101

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Clarify that declarative custom element definitions don't contain declarative shadow roots. #1101

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12 changes: 8 additions & 4 deletions proposals/Declarative-Custom-Elements-Strawman.md
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Original file line number Diff line number Diff line change
Expand Up @@ -9,7 +9,8 @@ First, with the proposed template instantiation API in mind, we imagined a HTML

```html
<definition name="my-element" constructor="MyElement">
<template shadowmode="closed">~</template>
<shadowoptions mode="open"></shadowoptions>
<template>~</template>
<script>
class MyElement extends HTMLElement { ~ }
</script>
Expand All @@ -22,7 +23,8 @@ This still requires having to repeat the constructor name twice. We can avoid th

```html
<definition name="my-element">
<template shadowmode="closed">~</template>
<shadowoptions mode="closed"></shadowoptions>
<template>~</template>
<script type="module">
export default class MyElement extends HTMLElement { ~ }
</script>
Expand All @@ -42,7 +44,8 @@ class /* default custom element */ extends HTMLElement {
const template = customElements.getTemplate(this);
if (!template)
return;
#shadowRoot = this.attachShadow({mode: template.getAttribute('shadowmode')});
const shadowOptions = customElements.getShadowOptions(this);
#shadowRoot = this.attachShadow(shadowOptions);
#templateInstance = #shadowRoot.appendChild(template.createInstance(#shadowRoot));
}
attributeChangedCallback(attributeName, oldValue, newValue, namespace) {
Expand All @@ -57,7 +60,8 @@ Note that the shadow root of the custom element is passed to createInstance's st

```html
<definition name="percentage-bar">
<template shadowmode="closed">
<shadowoptions mode="closed"></shadowoptions>
<template>
<div id="progressbar" role="progressbar" aria-valuemin="0" aria-valuemax="100" aria-valuenow="{{root.attributes.percentage.value}}">
<div id="bar" style="width: {{root.attributes.percentage.value}}%"></div>
<div id="label"><slot></slot></div>
Expand Down