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0 pointschaos_emergent1y ago0 comments

Holy shit, I’ve been writing python for 15 years and it’s the first time I’ve seen None used as an identity function. That’s nuts! How does it work under the hood? Does filter have a special case for evaluating None?

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echoangle1y ago

Yes, that’s just a special case. You can’t call None as a function.

https://docs.python.org/3/library/functions.html#filter

> If function is None, the identity function is assumed, that is, all elements of iterable that are false are removed.

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