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
|
error[E0392]: type parameter `A` is never used
--> $DIR/variance-unused-type-param.rs:6:19
|
LL | struct SomeStruct<A> { x: u32 }
| ^ unused type parameter
|
= help: consider removing `A`, referring to it in a field, or using a marker such as `PhantomData`
= help: if you intended `A` to be a const parameter, use `const A: /* Type */` instead
error[E0392]: type parameter `A` is never used
--> $DIR/variance-unused-type-param.rs:9:15
|
LL | enum SomeEnum<A> { Nothing }
| ^ unused type parameter
|
= help: consider removing `A`, referring to it in a field, or using a marker such as `PhantomData`
= help: if you intended `A` to be a const parameter, use `const A: /* Type */` instead
error: type parameter `T` is only used recursively
--> $DIR/variance-unused-type-param.rs:14:23
|
LL | enum ListCell<T> {
| - type parameter must be used non-recursively in the definition
LL | Cons(Box<ListCell<T>>),
| ^
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
= note: all type parameters must be used in a non-recursive way in order to constrain their variance
error: type parameter `T` is only used recursively
--> $DIR/variance-unused-type-param.rs:19:27
|
LL | struct SelfTyAlias<T>(Box<Self>);
| - ^^^^
| |
| type parameter must be used non-recursively in the definition
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
= note: all type parameters must be used in a non-recursive way in order to constrain their variance
error[E0392]: type parameter `T` is never used
--> $DIR/variance-unused-type-param.rs:22:19
|
LL | struct WithBounds<T: Sized> {}
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: type parameter `T` is never used
--> $DIR/variance-unused-type-param.rs:25:24
|
LL | struct WithWhereBounds<T> where T: Sized {}
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: type parameter `T` is never used
--> $DIR/variance-unused-type-param.rs:28:27
|
LL | struct WithOutlivesBounds<T: 'static> {}
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: type parameter `T` is never used
--> $DIR/variance-unused-type-param.rs:31:22
|
LL | struct DoubleNothing<T> {
| ^ unused type parameter
LL |
LL | s: SomeStruct<T>,
| - `T` is named here, but is likely unused in the containing type
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
= help: if you intended `T` to be a const parameter, use `const T: /* Type */` instead
error: aborting due to 8 previous errors
For more information about this error, try `rustc --explain E0392`.
|
