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Comment by heavenlyblue | Hacker News Reader

Given that it starts with a thing called "id" which is an implementation detail and probably should not be used for equality, it seems like this is a geniuinely well designed language :)

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id is not an implementation detail, it's a core built-in function of the language. The value that it returns is an implementation detail, but the properties of the value it returns are not and perfectly valid to rely on.

The "properties of the value it returns" are, by design, implementation-dependent. You're only supposed to use the id function if you need to know something about what's going on under the hood. The id function is working exactly as intended: it's exposing aspects of the implementation, if for some reason you need to know that stuff.

It would not be a positive change to sacrifice Python performance in order to make the output of id() more intuitive. I've spent many hundreds of hours coding Python and I don't believe I ever used that function or saw someone else use it.

`id()` is documented and mandated to exist, and the result provides guarantees that make it suitable for identity (not equality) checks[1] (although of course you should normally use the `is` operator). Pitfalls involving it are generally really pitfalls with understanding object lifetimes[2].

[1]: https://docs.python.org/3/library/functions.html#id

[2]: see e.g. https://stackoverflow.com/questions/52096582

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