How do I make a package in Scala private?

Question

If I have a package hierarchy in Scala like this:

package toplevel {
  package a {
    // some interesting stuff
  }

  package b {
    // more interesting stuff
  }

  package utility {
    // stuff that should not be accessible from the outside
    // and is not logically related to the project,
    // basically some helper objects
  }
}

how can I forbid the users of package toplevel to see or import package utility?

I tried with private[toplevel] package utility { ... but got this error: expected start of definition.

I've searched for this and was overwhelmed by false positives: everything I got was about making things package-private and this is not my question.

Why do you need that utility package? Wouldn't a private object be more suitable there? — znurgl, Dec 17 '15 at 09:25
I need the package to put some meta stuff that simplifies development of the other packages. Such stuff should probably be in a separate library but we don't want the extra dependencies. I'd like it to be a package because it contains 6 objects/classes already with probably more to come. Putting them all in one object would mean that they have to be in the same file and that would become too messy. — nedim, Dec 17 '15 at 09:40

score 4 · Accepted Answer · answered Dec 17 '15 at 19:14

4

You can't: packages don't have access levels.

Or rather, you can, by using OSGi and not exporting them, but this is a very heavy-weight solution if you don't need it for some other reason as well.

answered Dec 17 '15 at 19:14

Alexey Romanov

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score -1 · Answer 2 · answered Dec 17 '15 at 10:04

-1

To reach the same goal as private packages in Java you can use augmented access modifiers. Inside your package utility you restrict access with private[utility]. This way the package member is available only inside the package utility itself.

Hope that helps.

answered Dec 17 '15 at 10:04

Guenter Guckelsberger

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The question is how to make the entire package private, not how to make individual classes package-private. – nedim Dec 17 '15 at 10:47

score -2 · Answer 3 · edited May 23 '17 at 11:50

-2

    You can only define the enclosing package, within which the code is defined

Answered here.

edited May 23 '17 at 11:50

Community

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answered Dec 17 '15 at 10:19

Jet

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The question is how to make the entire package private, not how to make individual classes package-private. – nedim Dec 17 '15 at 10:47

How do I make a package in Scala private?

3 Answers3