New Twiddle

components.x-inner.js

import Ember from 'ember';

export default Ember.Component.extend({
}).reopenClass({
  positionalParams: "args"
});

components.x-outer.js

import Ember from 'ember';

export default Ember.Component.extend({
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{x-outer inner=(component "x-inner")}}
<br>
<br>

templates.components.x-inner.hbs

Inner: {{this.args}}|{{yield}}

templates.components.x-outer.hbs

{{@inner 1 2 3}}

{{#@inner}}wow{{/@inner}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}