title: Can't get Laravel associate to work
body: <p>I'm not quite sure if I understand the <a href="http://laravel.com/docs/4.2/eloquent#inserting-related-models" rel="noreferrer">associate</a> method in Laravel. I understand the idea, but I can't seem to get it to work. </p>
  
  <p>With this (distilled) code:</p>
  
  <pre><code>class User
  {
  
      public function customer()
      {
          return $this-&gt;hasOne('Customer');
      }
  
  }
  
  class Customer
  {
  
      public function user()
      {
          return $this-&gt;belongsTo('User');
      }
  
  }
  
  $user = new User($data);
  $customer = new Customer($customerData);
  
  $user-&gt;customer()-&gt;associate($customer);
  </code></pre>
  
  <p>I get a <code>Call to undefined method Illuminate\Database\Query\Builder::associate()</code> when I try to run this.</p>
  
  <p>From what I can read, I do it exactly as is stated in the docs. </p>
  
  <p>What am I doing wrong?</p>