Helper to Add Strings of Numbers - Positional vs Named Params

controllers.application.js

import Ember from 'ember';

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

helpers.add-numbers.js

import Ember from 'ember';

export function addNumbers(numbers, {base = 10}) {
  return numbers
  .map(n => parseInt(n, base))
  .reduce((result, value) => result + value, 0)
  .toString(base)
  .toUpperCase();
}

export default Ember.Helper.helper(addNumbers);

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{add-numbers "3" "4" "7" "8"}}
{{add-numbers "A3" "FF" base=16}}
<br>
<br>

twiddle.json

{
  "version": "0.13.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}