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by orf 3867 days ago
> What is useful about 'import lib; lib.re'?

Nothing, but it's a side effect of an awesome feature of Python: nothing being private. Which is incredibly useful. 'lib.re' is exactly the same case as 'lib.actual_library_function', why should Python add the ability to somehow stop these from being included? It would increase complexity for no gain.
1 comments
andreasvc 3867 days ago
You're just repeating that it is awesome and useful without saying why. I think distinguishing public & private variables offers more support for structured programming and is therefore desirable.
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orf 3867 days ago
> You're just repeating that it is awesome and useful without saying why.

Sorry, I thought you were asking why you are able to import other modules imports.

> I think distinguishing public & private variables offers more support for structured programming and is therefore desirable.

You can prefix attributes and functions with a single underscore to mark them as private, or a double underscore to make them more private (the attribute name gets mangled).

Anyway, Python doesn't have a enforced notion of privateness because it's a bad idea. By marking something as private you're saying "I, as a developer sat here writing this know better than all of the users of my library. Their lives may depend on using something I haven't exposed properly in my API, but too bad. I know best".

So you end up jumping through ridiculous hoops to access private properties (because even in languages with private, nothing is truly private), all because some guy thought he knows best a long time ago while writing the library you are using.

So a better approach (IMO) is to mark something as private with convention (a prefixed underscore), which means "this is private, don't depend on it", without restricting your access. You can drive a car, have sex, pay taxes, but not access a private variable? Bleugh.

That's more of a cultural thing though, I'm sure enforced private makes more sense in statically typed, compiled languages with lots of classes (and even then I would argue they are still bad for the reasons above), and matter more in huge codebases.

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