Is it possible to make a class `open` to its own module only but not to "the public"?

# announcements

[Marc Knaup]

Is it possible to make a class open to its own module only but not to "the public"?

[Ruckus]

You mean internal? https://kotlinlang.org/docs/reference/visibility-modifiers.html#packages

If you mark it internal, it is visible everywhere in the same module

[Marc Knaup]

no, internal only for the open part

[Marc Knaup]

the class itself should be public

[Ruckus]

Ah, I read "open" and thought "visible", sorry

[Mike]

Perhaps 'internal open' then?

[Marc Knaup]

Then the whole class is unusable outside the module 🙂

[Mike]

I guess we're not understanding the use case correctly, then.

[Mike]

Maybe a sealed class? But that obviously means everything has to be defined in one file.

The inheriting classes can be used outside the module but Noone can extend the 'parent'.

[Marc Knaup]

A class which is usable outside the module, and subclassable only within the module.
internal constructor should satisfy that 🙂

[Marc Knaup]

sealed class is limited to one file and also cannot be instantiated directly, be it in the same file or anywhere else.

[Mike]

Hmm, I think your idea of internal constructor should achieve that.

[Marc Knaup]

Wasn't my idea but yes 🙂

[Nikky]

you could make a internal open class and a (final) class that extends i without changes so you can use it outside, maybe ? possibly implementating a interface by delegation can trick the compiler here