var a = {n: 1};
a.x = a = {n: 2};
console.log(a.x);//undefined
var a, b, c, d;
a = b = c = d = {a: 1};
a.x = a = b.y = b = c.z = c = {}
console.log(a, b, c, d);/{},{},{},{a:1,x:{},y:{},z:{}}
參考: http://www.cnblogs.com/zichi/p/4630656.html
var a = {n: 1};
a.x = a = {n: 2};
console.log(a.x);//undefined
var a, b, c, d;
a = b = c = d = {a: 1};
a.x = a = b.y = b = c.z = c = {}
console.log(a, b, c, d);/{},{},{},{a:1,x:{},y:{},z:{}}
參考: http://www.cnblogs.com/zichi/p/4630656.html
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