Dijkstra's point is that you should start counting at 0, so if you want to generate the first five ordinals, you would write [0:5) which yields {0,1,2,3,4} as e

Dijkstra's point is that you should start counting at 0, so if you want to generate the first five ordinals, you would write [0:5) which yields {0,1,2,3,4} as expected.