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by zachbeane 1377 days ago
Also, some context from comp.lang.lisp is available at https://www.xach.com/naggum/articles/3250122499743574%40nagg...
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And to save everyone from having to read that:

| Can someone explain why the BOOLE function is a single function with sixteen ops rather than sixteen functions.

It's because there are only four possible inputs to a two-input boolean gate, and so there are only 2^4=16 possible boolean gates. Furthermore there is a straightforward representation of those gates as an ordered sequence of four bits that specify the output of the gate for each of the four possible combinations of inputs (though the CL standard does not actually require implementations to use this representation, and not all do).