anchor.diff:              p.medium-gray
                 p.large-gray.classroom-name= view.classroom.get('name')
                 br
  -              if view.classroom.owner.get('firstName')
  -                p.medium-gray.teacher-name= view.classroom.owner.get('firstName') + " " + view.classroom.owner.get('lastName')
  -              else if view.classroom.owner.get('name')
  -                p.medium-gray.teacher-name= view.classroom.owner.get('name')
  +              if view.classroom.owner
  +                if view.classroom.owner.get('firstName')
  +                  p.medium-gray.teacher-name= view.classroom.owner.get('firstName') + " " + view.classroom.owner.get('lastName')
  +                else if view.classroom.owner.get('name')
  +                  p.medium-gray.teacher-name= view.classroom.owner.get('name')
             else
               p.medium-gray(data-i18n="signup.classroom_not_found")
  -          
  +
         when 'teacher'
           // TODO
         when 'individual'
  
positive.code: 
        default
          p.medium-gray
            span Sign-up error, please contact 
            =" "
            a(href="mailto:support@codecombat.com") support@codecombat.com
            | .
  
negative.code:                 span.glyphicon.glyphicon-ok-circle.class-code-valid-icon
                else
                  span.glyphicon.glyphicon-remove-circle.class-code-valid-icon
  
          .render
            if _.isEmpty(view.signupState.get('classCode'))
              p.medium-gray
  