1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
var x : int; procedure P() modifies x; { x := 1000000; assert x > 0 && x < 2000000; x := x + 256; assert x == 1000256; x := 1000000000000; x := x + 100100; x := x - 100; assert x == 1000000100000; assert x < -123456789; // error }