Say tenatious:

> If you did $x = (@ary1,@ary2); you'd get the last value of @ary2.

Sorry, but that is not correct.

The comma operator propagates the scalar context to @ary1 and @ary2. In scalar context, the array expressions turn into the number of elements in each array. So if @ary1 has 10 elements and @ary2 has 20 elements, the expression above is like $x = (10,20), and $x is assigned the number 20.