<分区>
You are allowed to use free-standing blocks like this...
var something = 1;
{
var something = 2;
print("Inside: " + something);
}
print("Outside: " + something);
这是来自:http://eloquentjavascript.net/chapter3.html#p3c7ae609
但是有这样的 block 有什么意义呢?它有什么作用?