You can use Set with { } to create a set that you may use to loop over.

A Set contains no duplicates, otherwise it's just a collection of something.

With Integers

Set{14,22,12,53,2,11,66}->collect(i| DoSomthingWithAnInt(i))

With Strings

Set{'String', 'EmailAddress'}->collect(s| DoSomthingWithAString(s))

If you want to create a sequence of numbers (in order) you can use the Sequence operator.

Other names for set: collection of strings, array of numbers, static array, initialize array, list of numbers.

See also: OCLOperators Bag