title: what different between import * as module and import module in javascript
body: <p>When I write typescript:</p>
  
  <p>I have this code:</p>
  
  <pre><code>import * as express from 'express'
  </code></pre>
  
  <p>and the system gives me an error:</p>
  
  <pre><code>Type originates at this import. A namespace-style import cannot be called or constructed, and will cause a failure at runtime. Consider using a default import or import require here instead.
  </code></pre>
  
  <p>So, I change to:</p>
  
  <pre><code>import express from 'express'
  </code></pre>
  
  <p>what is the difference between them, why the first way can not called or constructed?</p>