 
   vm.acl = {
     isVisitor: ()->
-      return true if !$rootScope.user
+      return true if _.isEmpty $rootScope.user
       return !vm.acl.isParticipant()
     
     isParticipant: ()->
-      return false if !$rootScope.user
+      return false if _.isEmpty $rootScope.user
       participantIds = _.pluck vm.lookup['Participations'], 'participantId'
       return true if ~participantIds.indexOf($rootScope.user.id)
       return true if vm.acl.isOwner()
       return false
 
     isContributor: ()->
-      return false if !$rootScope.user
+      return false if _.isEmpty $rootScope.user
       return true if _.pluck(vm.lookup['Contributions'],'contributorId')
       .indexOf($rootScope.user.id) > -1
       # return vm.event?.contributorIds?.indexOf($rootScope.user.id) > -1
       return false
 
     isOwner: ()->
-      return false if !$rootScope.user
+      return false if _.isEmpty $rootScope.user
       return vm.event?.ownerId == $rootScope.user.id
   }
 


      next = i + 1
      if values[next] == 'contribute'
        if vm.acl.isParticipant() == false
          return vm.on.menuView(next, peek) # skip
        if vm.event.summary.myParticipation.isFullyParticipating

    .compact().value()

  vm.lookupByClass = (event, className, idOrArray)->
    if !(event?.id?) || !idOrArray
      return if _.isArray idOrArray then [] else false
    if _.isArray idOrArray
      check = _.chain( idOrArray )
