anchor.diff:        if view.state === 'enrolling'
           .progress.progress-striped.active
             .progress-bar(style="width: 100%") Joining class
  -  
  +    
         if view.state === 'unknown_error'
           .alert.alert-danger= view.stateMessage
       
  
positive.code:     else if campaign.sessions.size()
        - var lastSession = campaign.sessions.last();
        - var lastLevel = levels.findWhere({original: lastSession.get('level').original});
        - var levelURL = "/play/level/"+lastLevel.get('slug')+"?course="+courseInstance.get('courseID')+"&course-instance="courseInstance.id;
        a.btn.btn-success.btn-lg(href=levelURL)
          | Continue
      else
        - var firstLevel = levels.first();
        - var levelURL = "/play/level/"+firstLevel.get('slug')+"?course="+courseInstance.get('courseID')+"&course-instance="courseInstance.id;
        a.btn.btn-info.btn-lg(href=levelURL)
          | Start
negative.code:           - var classroomClass = classroom.justAdded ? 'just-added' : '';
            if classroom.justAdded
              .text-center.text-info Class successfully added!
  
            //- sigh
            div(class=classroomClass)
              h2
                span.spr= classroom.get('name')
                span.spr (#{(view.hocCourseInstance.get('aceConfig') || {}).language === 'python' ? 'Python' : 'JavaScript'})
  