title: requirejs reload javascript file
body: <p>I write a single web app using requirejs, i have no idea if reload js file frequently, the previous file that object has created can remove by browser or must close the page?</p>
  
  <p>main.js</p>
  
  <pre><code>btn.click(function() {
      require('./test.js?_r=' + Math.random());
  });
  </code></pre>
  
  <p>test.js</p>
  
  <pre><code>var a = [];
  for(var i = 0; i &lt; 1000000; i++) {
     a.push('myname ' + i);
  }
  </code></pre>