[issue29710] Incorrect representation caveat on bitwise operation docs

[Martin Panter]

Martin Panter <vadmium+py at gmail.com> added the comment:

I find the model in terms of “bit_length” hard to understand. You have to understand what bit_length returns, and why you added 1. Bit_length is awkward for negative numbers. It only uses the absolute value, which would give off-by-one problems with negative values, so I guess you added 1 to compensate.

I understand the bitwise operations as using two’s complement extended to an unlimited width, so that negative values have a series of ones for the most-significant bits. I presume this is what your “2-adic representation” is. Having this spelled out may have helped when I was learning Python.

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nosy: +martin.panter

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<https://bugs.python.org/issue29710>
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