为什么"**"绑定比否定更紧密? [英] Why does "**" bind more tightly than negation?

问题描述

我只是被以下情况所困扰:

I was just bitten by the following scenario:

>>> -1 ** 2
-1

现在，深入研究Python文档，很明显，这是故意的行为，但是为什么?我没有使用任何其他具有内置运算符功能的语言，但是没有尽可能严格地限制一元求反对我来说似乎是违反直觉的.

Now, digging through the Python docs, it's clear that this is intended behavior, but why? I don't work with any other languages with power as a builtin operator, but not having unary negation bind as tightly as possible seems dangerously counter-intuitive to me.

是否有这样做的理由?具有操作符的其他语言的行为是否类似?

Is there a reason it was done this way? Do other languages with power operators behave similarly?

推荐答案

该行为与数学公式中的行为相同，因此我不确定问题出在哪里，或者为什么它违反直觉.您能解释一下您在哪里看到了不同的东西吗? "**"总是绑定多于-":-x ^ 2与(-x)^ 2不同

That behaviour is the same as in math formulas, so I am not sure what the problem is, or why it is counter-intuitive. Can you explain where have you seen something different? "**" always bind more than "-": -x^2 is not the same as (-x)^2

只需使用(-1)** 2，就像在数学中一样.

Just use (-1) ** 2, exactly as you'd do in math.

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