Set operations on ruby arrays
Ruby provides some very interesting set operations on arrays.
given the two arrays A and B wich look like this
A = ["A", "B", "C", "D"]
B = ["C", "D", "E"]
There are three set operations we can use that union, intersection and difference.
Union
A | B
contains all elements from both sets without doublicates. So this results in ["A", "B", "C", "D", "E"]
Difference
A - B
contains all elements from set A that are not in set B. So this results in ["A", "B"]
Intersection
A & B
contains all elements that are in set A and in set B. So this results in ["C", "D"]
