title: Merge "Defaults" array with "Input" array? PHP Which Function?
body: <p>Lets say you are having a user provide information. </p>
  
  <pre><code>Array 1
  </code></pre>
  
  <p>But not all is required. So you have defaults.</p>
  
  <pre><code>Array 2
  </code></pre>
  
  <p>Does PHP have a function which will overwrite all array values of <code>Array 2</code> based on if they are supplied in <code>Array 1</code>, and not empty?</p>