Topic

WebIDL & Host Bindings

How WebIDL shapes the DOM APIs, types, brand checks, and conversion rules between JS and the platform.

webidlbindings

HTML

sample

<code>HTMLElement implements EventTarget</code>

CSS

sample

code { background: #0f172a; padding: 8px; }

JavaScript

sample

const url = new URL('https://example.com'); console.log(url.protocol)

Visualizer

WebIDL Bindings

IDL signatures and conversions.

Visualizer

WebIDL & Bindings

IDL defines shape, brand checks, and conversion rules between JS and host types.

live

Controls

Visualization

URL

constructor USVString url, optional USVString base

IDL conversions (e.g., USVString) sanitize input; brand checks ensure correct receiver.

Why this matters

Connect the dots between specs (HTML, CSS, WebIDL) and engine behaviors (parser, layout, GPU). Use the sandbox to reproduce each step with your own snippets.