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0 pointsshabble3y ago0 comments

even if I don't, I probably need to be able to understand and recognise them when other people do, in libraries/snippets etc that I depend on.

Not specifically a new feature, but I remember wasting a good bit of time when coming across a line that was essentially:

    return headers.get('x-foo') == settings.FOO_KEY is not None

and being extremely confused until discovering it was a use of comparison chaining[1] and was actually doing the right thing.

0 comments

> return headers.get('x-foo') == settings.FOO_KEY is not None

I'm a huge Python fanboy and this line is absolutely awful.

Comparison chains are great for stuff like "x < y < z" or "x == y == z", but the operators should never be mixed.

"Readability counts" is, IMO, the most important line in the Zen of Python, and that line is unreadable. I imagine it's equivalent to:

    return headers.get('x-foo') == settings.FOO_KEY and settings.FOO_KEY is not None

Which, admittedly, feels like a clumsy line of code, but it's at least readable.

Fair point, but then again, confusing code is everywhere :)

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