     |
Sequences
Sequence construction:
(1 to 10)[. mod 2 = 1] = (1, 3, 5, 7, 9)
($preamble, .//item)
Union, Intersection and Exception.
(1, 2, 3, 4) union (1, 3) = (1, 2, 3, 4)
(1, 2, 3, 4) intersect (1, 3) = (1, 3)
(1, 2, 3, 4) except (1, 3) = (2, 4)
Quantified expressions (some and every).