title: Accessing functions defined in system.js from HTML
body: <p>When using system.js, what's the right way to access a function from the global scope? For example, suppose we have this HTML:</p>
  
  <pre><code>&lt;form onsubmit="foo"&gt;
  &lt;input type="text" name="name" placeholder="name"&gt;
  &lt;/form&gt;
  &lt;script src="/lib/system.js"&gt;&lt;/script&gt;
  &lt;script&gt;
  SystemJS.import("/src/foo.js");
  &lt;/script&gt;
  </code></pre>
  
  <p>And we have this javascript:</p>
  
  <pre><code>function foo(form) { console.log("here"); }
  </code></pre>
  
  <p>How do you get SystemJS to export <code>foo</code> in such a way that it can be called when the form is submitted?</p>