title: Unexpected token (,) when mapping an array in ReactJS
body: <p>When I try to map an array in React (using this code):</p>
  
  <pre><code>const { loading, error, posts } = this.props;
      return(
      {posts.map(onePost =&gt; ({
          &lt;p key={onePost.id}&gt;{onePost.title}&lt;/p&gt;
  
      }))}
      );
  </code></pre>
  
  <p>I get an error:</p>
  
  <pre><code>    ERROR in ./src/client/app/mainGrid.jsx
  Module build failed: SyntaxError: C:/[redacted]/react/src/client/app/mainGrid.jsx: Unexpected token, expected , (15:8)
  
    13 |          return(
    14 |
  &gt; 15 |          {posts.map(onePost =&gt; ({
       |                ^
    16 |                  &lt;p key={onePost.id}&gt;{onePost.title}&lt;/p&gt;
    17 |
    18 |          }))}
  
   @ ./src/client/app/index.jsx 27:16-41
  </code></pre>
  
  <p>I have no idea why is this happening, everything looks fine to me.</p>