blob: d23c3ca0ee04aa7fefd7657eafd6707fcc2b474f (
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
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
object approximateUnion {
trait C[+T]
trait D
trait E
trait X[-T]
{
trait A extends C[A] with D
trait B extends C[B] with D
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{} )
val xtest: C[A | B] & D = x
val ytest: Some[C[A | B] & D] = y
}
{
trait A extends C[X[A]] with D
trait B extends C[X[B]] with D with E
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{})
val xtest: C[X[A & B]] & D = x
val ytest: Some[C[X[A & B]] & D] = y
}
}
object approximateUnion2 {
trait C[T]
trait D
trait E
trait X[-T]
{
trait A extends C[A] with D
trait B extends C[B] with D
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{})
val xtest: C[_ >: A & B <: A | B] & D = x
val ytest: Some[C[_ >: A & B <: A | B] & D] = y
}
{
trait A extends C[X[A]] with D
trait B extends C[X[B]] with D with E
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{})
val xtest: C[_ >: X[A | B] <: X[A & B]] & D = x
val ytest: Some[C[_ >: X[A | B] <: X[A & B]]] = y
}
}
object approximateUnion3 {
trait C[-T]
trait D
trait E
trait X[-T]
{
trait A extends C[A] with D
trait B extends C[B] with D
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{})
val xtest: C[A & B] & D = x
val ytest: Some[C[A & B] & D] = y
}
{
trait A extends C[X[A]] with D
trait B extends C[X[B]] with D with E
val coin = true
val x = if (coin) new A{} else new B{}
val y = Some(if (coin) new A{} else new B{})
val xtest: C[X[A | B]] & D = x
val ytest2: Some[C[X[A | B]] & D] = y
}
}
|