为什么 ( 无穷大 | 0 ) === 0？
我正在摆弄 JavaScript 中的按位运算符，我发现有一件事值得注意。
按位或运算符返回1如果两个输入位之一为1，则作为输出位。所以这样做 x | 0 总是返回 x，因为 | 0 没有效果：
( 1 | 0 ) === 1( 0 | 0 ) === 0
但是，当我计算 Infinity 时| 0，我得到0。在我看来，这是令人惊讶的，因为通过上面的计算应该得到Infinity。毕竟，( x | 0 ) === x。
我找不到 ECMAscript 规范中明确定义的位置，所以我想知道 ( Infinity | 0 ) === 0 到底意味着什么。也许这就是Infinity在内存中的存储方式？如果是这样，怎么可能仍然是做 | 0 操作会导致它返回 0，而 | 0 不应该做任何事情？
I'm fiddling around with bitwise operators in JavaScript and there is one thing I find remarkable.
The bitwise or operator returns 1 as output bit if one of the two input bits are 1. So doing x | 0 always returns x, because | 0 has no effect:
( 1 | 0 ) === 1( 0 | 0 ) === 0
However, when I calculated Infinity | 0, I got 0. This is surprising in my opinion, because by the above one should get Infinity. After all, ( x | 0 ) === x.
I cannot find where in the ECMAscript specification this is explicitly defined, so I was wondering what exactly implies that ( Infinity | 0 ) === 0. Is is perhaps the way Infinity is stored in memory? If so, how can it still be that doing a | 0 operation causes it to return 0 whereas | 0 should not do anything?
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位运算符仅适用于整数。
Infinity是浮点值，而不是整数。规范规定按位运算的所有操作数都会转换为整数（使用ToInt32 操作）在执行该操作之前。
ToInt32 操作表示：
Bitwise operators work on integers only.
Infinityis a floating-point value, not an integer.The spec says that all operands of bitwise operations are converted to integers (using the ToInt32 operation) before performing the operation.
The ToInt32 operation says:
进行需要
NaN和Infinity整数的数学和其他运算通常是一个坏主意。您将如何设置/清除Infinity中的一点？实际上，按位运算仅针对整数定义 - 并且整数没有
NaN或Infinity。Doing math and other operations that expect integers with
NaNandInfinityis usually a bad idea. How would you set/clear a bit from Infinity?Actually, bit-wise operations are only defined for integers - and integers do not have
NaNorInfinity.