Comments (3)
2..valueOf() == 2.0
输出22
如果这里是**2.valueOf()**就会报错
程序从左向右读,会把数字后面的第一个.识别为小数点,第二个点才会识别为操作符
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输出结果22:
原因:
1.2..valueOf()
中用到两个点是因为JS对数字后面的第一个点识别为小数点,第二个点识别为运算符,
2..valueOf()
得出的结果是数字2;
2.({z : 10, x : 20}).x)
中相当于求对象{z : 10, x : 20}
中x的值,x值为20,所以({z : 10, x : 20}).x)
结果是20;
3.得出(2..valueOf() + ({z : 10, x : 20}).x)
等于2+20
为22;
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比如:2.4.valueOf() 结果是2.4,因此及第一个点号是数字的,第二个点号 是点号运算符。
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