Protected case class constructor -> non-public apply

[dwijnand]

No description provided.

[dwijnand]

Coming back to protected apply: doesn't a protected apply method make the method available for subclasses of the case class? I guess I could write a test for that, either way. Done

[dwijnand]

@odersky do you consider it a bug that case classes with protected constructors are publicly constructible via the apply method?

Also, on a more technical note, is it preferable to keep things regular by just keeping things protected and qualified protected, or better to keep things sensical by making a protected constructor imply a private apply method?

[odersky]

It's a nice simplification for sure.

Is it true that the only effective change here is that if the constructor is protected, so is the apply method? Protected for the method does not really make sense here, since objects cannot be inherited. On the other hand protected also implies "package-private", and that's something we want. For clarity one might change this to a package private apply method instead. On the other hand protected is not wrong here, and it makes the code in desugar simpler.