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Comment by fiedzia | Hacker News Reader

> it's obvious that they are magic methods and not intended to be part of the public API

Is there an alternative API? No. This is public API regardless of anyone's intentions. Though "it's weird" is really not a very strong argument against it.

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Public API refers to the user of the class, not the implementer. You never call __init__ directly. __new__ allows modifying object creation itself for the implementer, but the user of the class will never call it.

There are private and public methods. Private methods are only supposed to be called within other methods, as in privately. Public methods are the ones that are normally called through the code, repl, by the user or whatever. You are not supposed to write `myclass.__add__(x)` anywhere except where you define the class itself and its methods.

There's actually 4 kinds:

  def foo(... # public
  def _foo(... # internal
  def __foo(... # munged
  def __foo__(... # magic

Internal is more convention as the language doesn't really do anything with it, but it does with munged, and magic methods are specifically for things implemented in the language.

Internal and munged don't exactly map to private and protected, but are kinda similar ish.

Oh right. I am not really into python, had read some doc about naming conventions some poitns.

In any case I actually like how one can use underscores to point on how exposed some method is supposed to be. Makes it simpler to actually know what to skip and what not.

There are several alternative API's. @dataclass is one, Pydantic offers another, there's also attrs, plus less general things like namedtuple.

Admittedly it's obnoxious when you've got habits for one and you're on a team that uses another--totally flies in the face of the zen re: "there should be only one obvious way to do things".

...but that was always a rather ambitious goal anyway. I'm ok navigating the forest of alternative API's if it means not being locked into something that I can only change by choosing an entirely different language. I'm happy that it's very easy to tell when somebody is mucking about with python internals vs when they're mucking about with some library or other.

@dataclass does a very specific subset of what overriding dunder methods does. It’s not duplicating an abstraction it’s layering them

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