title: Length array in array
body: <p>if I have an array like this:</p>
  
  <pre><code>$array = array(
       1,
       2,
       3,
       ["thing1", "thing2", "thing3"]
  );
  </code></pre>
  
  <p>how do I check what the lenght is of the array in the array ( ["thing1", "thing2", "thing3"] )?</p>