title: Overloading + operator for arrays in groovy
body: <p>I am a groovy newbie. Maybe this is a piece of cake, but I want to overload the + operator for arrays/lists to code like this</p>
  
  <pre><code>def a= [1,1,1]
  def b= [2,2,2]
  
  assert [3,3,3] == a + b 
  </code></pre>