title: Is it wrong to add instance variables to a Controller?
body: <p>If I want to share an object between multiple methods in a controller, is it wrong to create an instance var?  E.g.</p>
  
  <pre><code>class MyController {
      def index() {
          def user = verifyUserLogin()
          [messages:getMessages(user)]
      }
  
      private verifyUserLogin() {
          ...
          return user
      }
  
      private getMessages(user) {
          ...do something with `user`...
          return messages
      }
  }
  </code></pre>
  
  <p>would become</p>
  
  <pre><code>class MyController {
      private user
  
      def index() {
          verifyUserLogin()
          [messages:getMessages()]
      }
  
      private void verifyUserLogin() {
          ...
          this.user = user
          return
      }
  
      private getMessages() {
          ...do something with `user`...
          return messages
      }
  }
  </code></pre>