title: Concat array elements into new array
body: <p>I have a string which is separated by <code>&quot;/&quot;</code>, which I then split into an array. eg.</p>
  <pre><code>local string = 'Code/Github/Exercises'
  local array = std.split(string, &quot;/&quot;)
  
  // ['Code', 'Github', 'Exercises']
  </code></pre>
  <p>How do I then convert <code>array</code> so that I can get the output:</p>
  <pre><code>// ['Code', 'Code/Github', 'Code/Github/Exercises']
  </code></pre>