| Synopsis
| Computes the union of two sets, that is a set
which has all the elements of a and b. Repeated elements
are removed from the resulting set. The value intersect()
is understood to be the entire universe, and hence unions
including intersect() will simply return this term.
In its functional form, any arbitrary number of sets can be unioned.
In particular, union(a) = a, and union() = {}. |
| Examples
| > {1,2,3} union {2,3,4};
{1,2,3,4}
> {1,2,3} union {};
{1,2,3}
> {1,2,3} union intersect();
intersect()
|