self.slot->select(sl : SlotType1 | (not sl.name.oclIsUndefined()) and (sl.name = 'hash') )->forAll(sl : SlotType1 | 
	(not sl.valueList.oclIsUndefined()) and (sl.valueList.value->size()=1) ) and 
(self.slot->select(sl : SlotType1 | (not sl.name.oclIsUndefined()) and  (sl.name = 'hash') )->size()<2)