Unique GUID

components.accordion.content\.js

import Component from '@ember/component';

export default class extends Component {
  
}

components.accordion.heading\.js

import Component from '@ember/component';

export default class extends Component {
  
}

components.accordion\.js

import Component from '@ember/component';
import { guidFor } from '@ember/object/internals';

export default class extends Component {
  get contentId() {
    return guidFor(this);
  }
}

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>

<Accordion as |a|>
  <a.heading>Heading</a.heading>
  <a.content>Content</a.content>
</Accordion>

templates.components.accordion.content\.hbs

{{yield}} - content id: {{@contentId}}

templates.components.accordion.heading\.hbs

{{yield}} - content id: {{@contentId}}

templates.components.accordion\.hbs

{{yield	(hash
	heading=(component "accordion/heading" contentId=this.contentId)
  content=(component "accordion/content" contentId=this.contentId)
)}}

twiddle\.json

{
  "version": "0.17.0",
  "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/3.3.1/jquery.js",
    "ember": "3.17.0",
    "ember-template-compiler": "3.17.0",
    "ember-testing": "3.17.0"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}