var a:Array = [1, 2, 3, 4, 5];
var b:Array;
//clone a:
b = a.map(function(e:*, ...r):*{ return e });
/*
"...r" is a "rest" and stands for the two more arguments, the function in map(f:Function, target:Object = null) needs.
Full function would be: function (element:*, index:int, array:Array):*{return e};
*/