title: How to specify (optional) default props with TypeScript for stateless, functional React components?
body: <p>I'm trying to create a stateless React component with optional props and defaultProps in Typescript (for a React Native project). This is trivial with vanilla JS, but I'm stumped as to how to achieve it in TypeScript.</p>
  
  <p>With the following code:</p>
  
  <pre><code>import React, { Component } from 'react';
  import { Text } from 'react-native';
  
  interface TestProps {
      title?: string,
      name?: string
  }
  
  const defaultProps: TestProps = {
      title: 'Mr',
      name: 'McGee'
  }
  
  const Test = (props = defaultProps) =&gt; (
      &lt;Text&gt;
          {props.title} {props.name}
      &lt;/Text&gt;
  );
  
  export default Test;
  </code></pre>
  
  <p>Calling <code>&lt;Test title="Sir" name="Lancelot" /&gt;</code> renders "Sir Lancelot" as expected, but <code>&lt;Test /&gt;</code> results in nothing, when it should output 
  "Mr McGee".</p>
  
  <p>Any help is greatly appreciated.</p>