anywidget

Minor Changes

• Migrate to Svelte 5 signals API (#869)

  This release deliberately contains backwards-incompatible changes. To avoid automatically picking up releases like this, you should either be pinning the exact version of @anywidget/svelte in your package.json file or be using a version range syntax that only accepts patch upgrades such as ~0.0.1.

  The @anywidget/svelte now uses Svelte 5's new runes reactivity system (aka signals). The context-based implementation has been replaced with reactive model bindings using createSubscriber.

  Update your Svelte dependency to version 5:

  npm install svelte@^5.0.0
  

  Ensure Svelte 5 runes are enabled in your bundler configuration:

  // rolldown.config.js or rollup.config.js
  svelte({
    compilerOptions: {
      runes: true,
    },
  });
  

  The previous API used Svelte 4 and exposed model values via the stores proxy:

  <script>
    import { stores } from "@anywidget/svelte";
    let { count } = stores;
  </script>
  
  <button on:click={() => $count += 1}>Count is {$count}</button>
  

  With Svelte 5, @anywidget/svelte now uses direct reactive bindings and the $props() rune:

  <script>
    /** @type {{ bindings: { count: number } }} */
    let { bindings } = $props();
  </script>
  
  <button on:click={() => bindings.count++}>Count is {bindings.count}</button>

  This is a breaking change. The old stores API and getContext-based access are no longer supported. You must update your components to use the new bindings prop via $props().

  See manzt/ipyfoo-svelte for a complete example.