diff options
-rw-r--r-- | test/files/neg/bug1279a.check | 6 | ||||
-rw-r--r-- | test/files/neg/bug1279a.scala | 38 | ||||
-rw-r--r-- | test/files/neg/saito.check | 2 |
3 files changed, 45 insertions, 1 deletions
diff --git a/test/files/neg/bug1279a.check b/test/files/neg/bug1279a.check new file mode 100644 index 0000000000..48b84e0f46 --- /dev/null +++ b/test/files/neg/bug1279a.check @@ -0,0 +1,6 @@ +bug1279a.scala:34: error: no type parameters for method all4Impl: (M{type T <: U})Stream[M{type T <: U}] exist so that it can be applied to arguments (first.selfType) + --- because --- +result type Stream[M{type T <: U}] is incompatible with expected type Stream[M{type T <: U}] + def all4Impl[U](first: M {type T <: U}): Stream[M {type T <: U}] = Stream.cons(first, all4Impl(first.next)) + ^ +one error found diff --git a/test/files/neg/bug1279a.scala b/test/files/neg/bug1279a.scala new file mode 100644 index 0000000000..7568d3afcd --- /dev/null +++ b/test/files/neg/bug1279a.scala @@ -0,0 +1,38 @@ +// providing the type parameter in the recursive call to all4Impl +// avoids the problem + + +// covariant linked list +abstract class M +{ self => + + type T + final type selfType = M {type T <: self.T} + type actualSelfType >: self.type <: selfType + + def next: selfType + + + // I don't understand why this doesn't compile, but that's a separate matter + // error: method all2 cannot be accessed in M.this.selfType + // because its instance type => Stream[M{type T <: M.this.selfType#T}] + // contains a malformed type: M.this.selfType#T + // def all2: Stream[M {type T <: self.T}] = Stream.cons(self: actualSelfType, next.all2) + + + // compiles successfully + // def all3: Stream[M {type T <: self.T}] = all3Impl(self: actualSelfType) + // private def all3Impl(first: M {type T <: self.T}): Stream[M {type T <: self.T}] = Stream.cons(first, all3Impl(first.next)) + + + + def all4: Stream[M {type T <: self.T}] = Unrelated.all4Impl[T](self: actualSelfType) +} + +object Unrelated +{ + def all4Impl[U](first: M {type T <: U}): Stream[M {type T <: U}] = Stream.cons(first, all4Impl(first.next)) + +// compiles successfully +// def all4Impl[U](first: M {type T <: U}): Stream[M {type T <: U}] = Stream.cons(first, all4Impl[U](first.next)) +} diff --git a/test/files/neg/saito.check b/test/files/neg/saito.check index 51964e6fd4..061a45b76e 100644 --- a/test/files/neg/saito.check +++ b/test/files/neg/saito.check @@ -1,4 +1,4 @@ -saito.scala:10: error: class A cannot be instantiated because it does not conform to its self-type B with A +saito.scala:10: error: class A cannot be instantiated because it does not conform to its self-type A with B val a: A = new A; // should not be allowed ^ one error found |