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// These are members of class bar.C, completely unrelated to class foo.A.
// The types shown below include types defined within foo.A which are:
//
// - qualified private
// - qualified protected
// - object protected
//
// val a : foo.A = { /* compiled code */ }
// val xprot1 : java.lang.Object with foo.A.FooProt1 = { /* compiled code */ }
// val xprot2 : java.lang.Object with foo.A.FooProt2 = { /* compiled code */ }
// val xprot3 : java.lang.Object with foo.A.FooProt3 = { /* compiled code */ }
// val xprot4 : java.lang.Object with foo.A.FooProt4 = { /* compiled code */ }
// val xpriv3 : java.lang.Object with foo.A.FooPriv3 = { /* compiled code */ }
// val xpriv4 : java.lang.Object with foo.A.FooPriv4 = { /* compiled code */ }
//
// Indeed it will tell me a type which I cannot access:
//
// scala> new bar.C
// res0: bar.C = bar.C@1339a0dc
//
// scala> res0.xpriv3
// res1: java.lang.Object with res0.a.FooPriv3 = bar.C$$anon$29@39556aec
//
// scala> new res0.a.FooPriv3
// <console>:9: error: trait FooPriv3 in class A cannot be accessed in foo.A
// new res0.a.FooPriv3
// ^
// Looking at how the compiler prints the types of those vals, one
// develops a suspicion how some of it is being allowed:
//
// val xpriv4: C.this.a.FooPriv4
// val xpriv3: C.this.a.FooPriv3
// val xprot4: C.this.a.FooProt4
// val xprot3: C.this.a.FooProt3
// val xprot2: C.this.a.FooProt2
// val xprot1: C.this.a.FooProt1
//
// That is, "this" is in the prefix somewhere, it's just not a "this"
// which has any bearing.
package foo {
class A {
trait Foo
protected trait FooProt1
protected[this] trait FooProt2
protected[foo] trait FooProt3
protected[A] trait FooProt4
private trait FooPriv1
private[this] trait FooPriv2
private[foo] trait FooPriv3
private[A] trait FooPriv4
type BarProt1 = FooProt1
type BarProt2 = FooProt2
type BarProt3 = FooProt3
type BarProt4 = FooProt4
// type BarPriv1 = FooPriv1
// type BarPriv2 = FooPriv2
type BarPriv3 = FooPriv3
type BarPriv4 = FooPriv4
def fprot1(x: FooProt1) = x
def fprot2(x: FooProt2) = x
def fprot3(x: FooProt3) = x
def fprot4(x: FooProt4) = x
// def fpriv1(x: FooPriv1) = x
// def fpriv2(x: FooPriv2) = x
def fpriv3(x: FooPriv3) = x
def fpriv4(x: FooPriv4) = x
val yprot1 = new FooProt1 { }
val yprot2 = new FooProt2 { }
val yprot3 = new FooProt3 { }
val yprot4 = new FooProt4 { }
// val ypriv1 = new FooPriv1 { }
// val ypriv2 = new FooPriv2 { }
val ypriv3 = new FooPriv3 { }
val ypriv4 = new FooPriv4 { }
def fpriv_alt1(x: FooPriv1) = 0 // !!! isn't the private type now in the signature of the (public) method?
def fpriv_alt2(x: FooPriv2) = 0 // !!! isn't the private[this] type now in the signature of the (public) method?
}
// Same package, subclass
class B extends A {
val xprot1 = new BarProt1 { }
val xprot2 = new BarProt2 { }
val xprot3 = new BarProt3 { }
val xprot4 = new BarProt4 { }
// val xpriv1 = new BarPriv1 { }
// val xpriv2 = new BarPriv2 { }
val xpriv3 = new BarPriv3 { }
val xpriv4 = new BarPriv4 { }
override def fprot1(x: BarProt1) = x
override def fprot2(x: BarProt2) = x
override def fprot3(x: BarProt3) = x
override def fprot4(x: BarProt4) = x
// override def fpriv1(x: BarPriv1) = x
// override def fpriv2(x: BarPriv2) = x
override def fpriv3(x: BarPriv3) = x
override def fpriv4(x: BarPriv4) = x
}
// Same package, unrelated class
class C {
val a = new A
import a._
val xprot1 = new BarProt1 { }
val xprot2 = new BarProt2 { }
val xprot3 = new BarProt3 { }
val xprot4 = new BarProt4 { }
// val xpriv1 = new BarPriv1 { }
// val xpriv2 = new BarPriv2 { }
val xpriv3 = new BarPriv3 { }
val xpriv4 = new BarPriv4 { }
}
}
package bar {
// Different package, subclass
class B extends foo.A {
val xprot1 = new BarProt1 { }
val xprot2 = new BarProt2 { }
val xprot3 = new BarProt3 { }
val xprot4 = new BarProt4 { }
// val xpriv1 = new BarPriv1 { }
// val xpriv2 = new BarPriv2 { }
val xpriv3 = new BarPriv3 { }
val xpriv4 = new BarPriv4 { }
override def fprot1(x: BarProt1) = x
override def fprot2(x: BarProt2) = x
override def fprot3(x: BarProt3) = x
override def fprot4(x: BarProt4) = x
// override def fpriv1(x: BarPriv1) = x
// override def fpriv2(x: BarPriv2) = x
override def fpriv3(x: BarPriv3) = x
override def fpriv4(x: BarPriv4) = x
}
// Different package, unrelated class
class C {
val a = new foo.A
import a._
val xprot1 = new BarProt1 { }
val xprot2 = new BarProt2 { }
val xprot3 = new BarProt3 { }
val xprot4 = new BarProt4 { }
// val xpriv1 = new BarPriv1 { }
// val xpriv2 = new BarPriv2 { }
val xpriv3 = new BarPriv3 { }
val xpriv4 = new BarPriv4 { }
}
}
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