I’ve been working on an arbitrary-precision numeric class (in Python) that stores numbers in what amounts to base-256 — that is to say, in machine-native binary. It differs from the variable-length integers in Python by supporting fractions (and from Python’s Decimal number type by being binary).

It occurred to me I could implement multiplication with a lookup table rather than actually doing the math (at the CPU level, that may be what in fact is going on). So, I thought I’d compare the two implementations.

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