title: React .- reduce() within JSX not rendering
body: <p>I have following code within render method:</p>
  
  <pre><code>return (&lt;select&gt;
  {[...Array(24).keys()].reduce((acc, item) =&gt; `${acc} &lt;option value="${item}"&gt;${item}&lt;option&gt;`, '')}
  &lt;/select&gt;);
  </code></pre>
  
  <p>acc variable contains all options, and reduce() function has implicit return but no options are displayed. What is explanation behind this?</p>
  
  <p>I was able to make this work with .map(), I'm just curious what is the problem with the reduce function in the above example.</p>
  
  <pre><code>&lt;select&gt;
  {[...Array(24).keys()].map(hour =&gt; {
  return &lt;option value={hour} key={hour}&gt;{hour}&lt;/option&gt;
  })
  }
  &lt;/select&gt;
  </code></pre>
  
  <p>Thanks</p>