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Comment by hdjrudni | Hacker News Reader

> Otherwise you've got one object that's actually two types: the object half-initialised and the object fully initialised, and it's very easy to confuse the two.

You said it yourself -- if you feel like you have two objects, then literally use two objects if you need to split it up that way, FooBarBuilder and FooBar. That way FooBar is always fully built, and if FooBarBuilder needs to do funky black magic, it can do so in `build()` instead of `__init__`.

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I mean, you can do that (and it kight be useful if you want to seperate where the construction arguments are from where when the initialisation happens), but I don't understand why not just do it in init instead of build. It's not all that special, it's literally just a method that's called when you make an instance of the class, if you need to do it before you use the class, just make it happen when you make the class.

no thanks, that's how we end up with FactoryFactory. If the work needs to be done upon startup, then it needs to be done. if it is done in response to a later event, then it been done later.

For me the point is that __init__ is special - it's the language's the way to construct an object. If we want to side-effecting code we can with a non-special static constructor like

class Foo @classmethod def connect(): return Foo()._connect()

The benefit is that we can choose when we're doing 1) object construction, 2) side-effecting 3) both. The downside is client might try use the __init__() so object creation might need to be documented more than it would otherwise

Init isn't really special (especially compared to e.g. __new__). It has no special privileges, it's just a method that is called when you construct an instance of the class.

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