Why does ~False give -1 and ~True -2?

Question

I always thought that ~ was equivalent to not in Python, but I had a bug that made me find out this. Could someone explain to me what that is?

Thanks

Does this answer your question? [The tilde operator in Python](https://stackoverflow.com/questions/8305199/the-tilde-operator-in-python) — Ani, Mar 23 '21 at 15:02
False and True are also numbers 0 and 1. `~` is *bitwise* negation. — Michael Butscher, Mar 23 '21 at 15:03

score 2 · Answer 1 · answered Mar 23 '21 at 15:05

From the official documentation:

The unary ~ (invert) operator yields the bitwise inversion of its integer argument. The bitwise inversion of x is defined as -(x+1). It only applies to integral numbers.

As to why ~False would be -1, it's because for historical reasons False == 0 and True == 1 (they're not identical but they are equal, and bool is a subclass of int). If you apply the formula above, you get ~False => -(False + 1) => -(0+1) => -1, QED.

Why does ~False give -1 and ~True -2?

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