title: Super expression must either be null or a function, not object
body: <p>I get <strong>Super expression must either be null or a function, not object</strong> error when I run <strong>index.js</strong></p>
  
  <p>I see another post <a href="https://stackoverflow.com/questions/37328215/super-expression-must-either-be-null-or-a-function-not-object-error">here</a> with similar error message. But looks like that is related to react!</p>
  
  <h1>base.js</h1>
  
  <pre><code>   export default class Base{
          constructor(title){
              console.log(title);
          }
      }
  </code></pre>
  
  <h1>Class1.js</h1>
  
  <pre><code>import * as Base from './base';
  
  export default class Class1 extends Base{
      constructor(title){
          super(title);
      }
  }
  </code></pre>
  
  <h1>index.js</h1>
  
  <pre><code>import * as Class1 from './class1';
  'use strict';
  
  function check() {
      var c = new Class1('from Index.js');
  }
  
  check();
  </code></pre>
  
  <h1>.babelrc</h1>
  
  <p>{
      "presets": [
          "es2015",
          "stage-1"
      ]
  }</p>
  
  <h1>dependencies</h1>
  
  <pre><code>dependencies": {
      "babel-cli": "^6.24.1",
      "babel-eslint": "^7.2.3",
      "babel-plugin-add-module-exports": "^0.2.1",
      "babel-plugin-syntax-export-extensions": "^6.13.0",
      "babel-plugin-transform-runtime": "^6.23.0",
      "babel-preset-es2015": "^6.24.1",
      "babel-preset-stage-1": "^6.24.1",
      "babel-register": "^6.24.1"
    }
  </code></pre>
  
  <p>Please help! Thanks in advance !</p>