blob: 517408886d927c381979bc97a818fa99298ff99f (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
// See also pos/override-object-yes.scala
package case1 {
// Missing interface in overriding object
class Bippy { def f = 1 }
trait Bippo
trait Foo {
object Bar extends Bippy with Bippo { override def f = 2 }
def f(x: Bippo)
def g = f(Bar)
}
trait Foo2 extends Foo {
override object Bar extends Bippy { // err
override def f = 3
}
}
// type mismatch in member
trait Quux1 { object Bar { def g = 55 } }
trait Quux2 extends Quux1 { override object Bar { def g = "abc" } } // err
// still can't override final objects!
trait Quux3 { final object Bar { } }
trait Quux4 extends Quux3 { override object Bar } // err
}
// type parameter as-seen-from business
package case2 {
// invariance (see pos for the covariant case)
class Bar[T]
class Foo[T] {
object A extends Bar[T]
}
class Baz[S] extends Foo[S] {
override object A extends Bar[S]
}
class P1 extends Foo[Traversable[String]]
class P2 extends P1 {
override object A extends Bar[List[String]] // err
}
}
// Both overridden and overriding members must be objects, not vals with a module type
object SI9574 {
object Foo
object Bar
trait A { def x: Foo.type }
trait B extends A { def x: Bar.type } // should not compile (SI-9574)
trait C extends A { override object x }
trait D { object x; def y = x }
trait E extends D { override val x: super.x.type = y } // OK but doesn't need object subtyping exception
}
|
