Syntax
union(array, array,[array],… )
Description
The union() function returns a set that contains all items from the original array, and all items from the specified array(s).
If an item is present in more than one array, the result will contain only one appearance of this item.
Example
a=[1,2,3,4,4,4] b=[3,4,5,6] c=[7,8] println(union(a,b,c)) [1, 2, 3, 4, 5, 6, 7, 8]