title: Typescript error "Cannot find name"
body: <p>I am trying to use the <code>big.js</code> library, whose definition is <a href="https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/big.js/big.js.d.ts" rel="nofollow">here</a>.</p>
  
  <p>Now, this line works:</p>
  
  <pre><code>const CONSTANT_1 = new Big(0);
  </code></pre>
  
  <p>Whilst this line:</p>
  
  <pre><code>const CONSTANT_2 : Big = new Big(0);
  </code></pre>
  
  <p>causes the error:</p>
  
  <pre><code>error TS2304: Cannot find name 'Big'.
  </code></pre>
  
  <p>What's the problem?</p>