: test -1 -1 [ 1 ] [ 2 ] [ 3 ] [ 4 ] 4wayIf .s drop 0 0 [ 1 ] [ 2 ] [ 3 ] [ 4 ] 4wayIf .s drop -1 0 [ 1 ] [ 2 ] [ 3 ] [ 4 ] 4wayIf .s drop 0 -1 [ 1 ] [ 2 ] [ 3 ] [ 4 ] 4wayIf .s drop ;