a := [1,2,3,4] ----> list(4) a1 := a[1:2] ----> list(1) 1 every write(!a1) ----> none a2 := a[3:0] ----> list(2) 3 4 every write(!a2) ----> none a4 := a[2:2] ----> list(0) every write(!a4) ----> none a5 := a[0-:2] ----> list(2) 3 4 every write(!a5) ----> none a3 := a[0:3] ----> list(2) 3 4 every write(!a3) ----> none Run-time error 101 at line 20 in std35.icn integer expected offending value: &null