New Twiddle

components.my-component.js

import Ember from 'ember';

const MyComponent = Ember.Component.extend({
});

MyComponent.reopenClass({
  positionalParams: ['state', 'setState']
});

export default MyComponent;

components.with-state.js

import Ember from 'ember';

const WithState = Ember.Component.extend({
  init() {
    this._super(...arguments);
    
    const {
      propName,
      propUpdaterName,
      initialValue,
    } = this
    
    this[propName] = initialValue
    this[propUpdaterName] = newValue => this.set(propName, newValue)
  },
});

WithState.reopenClass({
  positionalParams: ['componentName', 'propName', 'propUpdaterName', 'initialValue'],
});

export default WithState;

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>
{{outlet}}
<br>
<br>

{{!-- normal --}}
{{my-component state=0 setState=(action (action (mut state)) 5)}}

{{!-- api sketch, doesn't work since we can't dynamically generate components --}}
{{!--
{{#with (state "count" "setCount" 0) as |enhance|}}
	{{#enhance (component 'some-component') as |enhancedComponent|}}
    {{enhancedComponent}}
  {{/enhance}}
{{/with}}
--}}

{{!-- refined version that works in ember --}}
{{#with-state 'my-component' 'count' 'setCount' 0 as |my-component|}}
  {{component my-component}}
{{/with-state}}

templates.components.my-component.hbs

{{!--<button type="button" onclick={{action setState 5}}>{{state}}</button>--}}
{{log state}}
{{log setState}}

templates.components.with-state.hbs

{{yield (component componentName
  [propName]=(get this propName)
  [propUpdaterName]=(get this propUpdaterName)
)}}

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0",
    "ember-spread": "1.2.2"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}