title: How to unset a function definition just like we unset a variable?
body: <p>I want to define a function and unset it after its use just like we do with variables.</p>
  
  <pre><code>$a = 'something';
  unset($a);
  echo $a; // outputs nothing
  </code></pre>
  
  <p>Just like this if i declare a function <strong>callMethod()</strong>, is there a way to unset it?</p>