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Comment by aeturnum | Hacker News Reader

Many of these things are annoying, but I wanna check something....

Lists in python are called lists because they're linked lists right? They are not called arrays because they are a different data structure.

Edit: Well TIL! Thanks everyone.

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> Lists in python are called lists because they're linked lists right?

No. At the C level in the interpreter they are arrays of object pointers.

> They are not called arrays because they are a different data structure.

No. They're not called arrays because Python uses the name "array" for something else:

https://docs.python.org/3/library/array.html

How widely are Python arrays used in practice?

I haven't had much occasion to use them. I suspect that most use cases nowadays where the speed advantage is needed involve numerical computing where the user is probably using a library like numpy or scipy and will use their array implementation, not the built-in Python one. However, arrays have been around in Python since very early on, when those other numerical libraries didn't exist, so the array built-in might have gotten more use then.

No, lists are implemented in CPython as an regular, contiguous array of PyObject. There is an array library (https://docs.python.org/3/library/array.html) for more efficient storage, comparable to JS's Uint8Array and friends.

lists are arrays with different data types allowed per index

Nope.

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