I long this is long overdue, but even though there aren't any arrays in nexus, you can use lists instead:
Dim(list number);
Empty(list);
ClearSelect(list); //they "free", delete, the given list
setN(list, place, element); //it adds an element on that place (I think it only handles numbers... but I never gave it a thorough test)
getN(list, place);
pickN(list,place); //they returns the element located on "place"
and many more ADT functions. Although not arrays, they're close enough.