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A comment on Why does a = a[0] = [0] create a self-referential list in Python?.

Re:Why does a = a[0] = [0] create a self-referential list in... by anitil on Thursday November 18, 2021 @05:06PM (#29271238)
I'm amazed at how long I've been working in python and never known that assignment works in this way. I suppose I just avoid parts of the language that I don't understand.

Looking through the archives, it's a really interesting blog in general

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Re:Why does a = a[0] = [0] create a self-referential list in... by heavyset_go on Thursday November 18, 2021 @08:20PM (#29272718)
Some languages wear the things that make you go WTF on their sleeves. In contrast, Python's surprises pop up slowly over time, and in places where you'd least expect them.
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Re:Why does a = a[0] = [0] create a self-referential list in... by SOLAR_FIELDS on Friday November 19, 2021 @12:22AM (#29274097)
I wonder if it’s because of their subtlety. I assume you are referencing JavaScript, where the warts are impossible to ignore because you can’t write an everyday program as a beginner without running into them. This sort of thing from the article is just not something I would typically be trying to do in the normal course of shuffling data around.
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Re:Why does a = a[0] = [0] create a self-referential list in... by klyrs on Thursday November 18, 2021 @05:50PM (#29271617)
I mean, it generally looks like a terrible idea, so absent of malice to the reader (or code golf shenanigans) nobody would do this. Not a surprise that the behavior is surprising...
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Re:Why does a = a[0] = [0] create a self-referential list in... by londons_explore on Thursday November 18, 2021 @06:54PM (#29272147)
It's fallout of the fact that assignment must be a statement, and cannot be an expression.

Eg. This is wrong in python, while it would be allowed in c-like languages

    print(a=5)
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Re:Why does a = a[0] = [0] create a self-referential list in... by orf on Thursday November 18, 2021 @06:57PM (#29272178)
It’s possible now with the walrus operator though:

    print(a:=5)
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