var .a1 = [1, 2, 3, "abc"]
val .a2 = series 4..10
val .a3 = .a1 ~ .a2

writeln "initial values ..."
writeln ".a1: ", .a1
writeln ".a2: ", .a2
writeln ".a3: ", .a3
writeln()

.a1[4] = .a2[4]
writeln "after setting .a1[4] = .a2[4] ..."
writeln ".a1: ", .a1
writeln ".a2: ", .a2
writeln ".a3: ", .a3
writeln()

writeln ".a2[1]: ", .a2[1]
writeln()

writeln "using index alternate ..."
writeln ".a2[5; 0]: ", .a2[5; 0]
writeln ".a2[10; 0]: ", .a2[10; 0]
writeln()