title: How can I create a new operator in PHP?
body: <p>I see myself doing the following code for default assigment all the type on PHP</p>
  
  <pre><code>$variable = $variable ? $variable : 'default value';
  </code></pre>
  
  <p>I know that with 5.3 I can do</p>
  
  <pre><code>$variable = $variable ?: 'default value';
  </code></pre>
  
  <p>I would like to further simplify it by being able to just do</p>
  
  <pre><code>$variable ?= 'default value';
  </code></pre>
  
  <p>and have the variable reassigned in case it evaluates to false. Is it possible to create that assignment? Do I have to compile my own version of php to do that?</p>