component "convert-by"

components.convert-by.js

import Ember from 'ember';

let MyComponent = Ember.Component.extend({
  tagName: null,
  onInit: Em.on('init', function() {
    this.set('raw', this.func(this.get('value')));
  }),
  raw: null,
  value: null,
  func: function() {
    return { test: 0 };
  }
});

MyComponent.reopenClass({
  positionalParams: ['func', 'value']
});

export default MyComponent;

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  utils: Em.inject.service(),
  appName: 'Ember Twiddle',
  ddd(value) {
     return { test: value + 678, value: 555 };
  },
  actions: {
    myFunc(value) {
     return { test: value };
    }
  }
});

helpers.my-helper.js

import Ember from 'ember';

export default Ember.Helper.helper(function([param, ...rest]) {
  return `<b>${param}{{yield}}</b>`;
});

router.js

import Ember from 'ember';
import config from './config/environment';

const Router = Ember.Router.extend({
  location: 'none',
  rootURL: config.rootURL
});

Router.map(function() {
});

export default Router;

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
{{#convert-by utils.convertNumber number as |raw|}}
  {{raw.test}} --- {{raw.value}}
{{/convert-by}}
{{!--#convert-by myTestFunc 123 as |raw|}}
  {{raw.test}}
{{/convert-by--}}
{{#convert-by as |raw|}}
  {{raw.test}}
{{/convert-by}}
<br>

templates.components.convert-by.hbs

{{yield raw}}

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}