var arr:Array = ["abc","def"];

arr.insert("ght",atIndex:2);

1)整个元组进行遍历

for begnin arr.enumerate() {

print(begn);

}

2)遍历下标和元素

for (index,element)in arr.enumerate(){

print(index);

print(element);

}

2.数组copy

var str4 = arr;

print(str4);

arr.removeLast();

print(arr);

print(str4);

运行结果:arr变化，str4没有变化