New Twiddle

components.my-component\.js

import Component from '@glimmer/component';
import { tracked } from '@glimmer/tracking';

export default class extends Component {
  @tracked counter = 0;
  constructor() {
    super(...arguments);
    this.startPolling();
  }
  willDestroy() {
    super.willDestroy(...arguments);
    this.stopPolling();
  }
  _poll() {
    this.counter++;
    this._timer = setTimeout(() => this._poll(), 1000);
  }
  startPolling() {
    this.stopPolling();
    this._timer = setTimeout(() => this._poll(), 1000);
  }
  stopPolling() {
    clearTimeout(this._timer);
  }
}

controllers.application\.js

import Controller from '@ember/controller';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
}

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
<MyComponent as |foobar|>
  {{log foobar.counter}}
  <data>{{foobar.counter}}</data>
</MyComponent>
<br>
<br>

templates.components.my-component\.hbs

{{yield (hash counter=this.counter)}}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}