1module sets;
2type
3 Color = (RED, BLUE, GREEN);
4 ColorSet = set of Color;
5var
6 s : ColorSet;
7
8procedure p (var s : ColorSet);
9begin
10 s := ColorSet{RED, BLUE};
11end p;
12
13begin
14 p(s);
15 if BLUE in s then
16 s := s - ColorSet{BLUE};
17 end;
18end sets.
19