-
Notifications
You must be signed in to change notification settings - Fork 32
/
trait-underscore.rs
89 lines (79 loc) · 1.88 KB
/
trait-underscore.rs
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
// Test that `impl MyTrait<'_> for &i32` is equivalent to `impl<'a,
// 'b> MyTrait<'a> for &'b i32`.
//
//@ run-pass
#![allow(warnings)]
trait MyTrait<'a> { }
// This is equivalent to `MyTrait<'a> for &'b i32`, which is proven by
// the code below.
impl MyTrait<'_> for &i32 {
}
// When called, T will be `&'x i32` for some `'x`, so since we can
// prove that `&'x i32: for<'a> MyTrait<'a>, then we know that the
// lifetime parameter above is disconnected.
fn impls_my_trait<T: for<'a> MyTrait<'a>>() { }
fn impls_my_trait_val<T: for<'a> MyTrait<'a>>(_: T) {
impls_my_trait::<T>();
}
fn random_where_clause()
where for<'a, 'b> &'a i32: MyTrait<'b> { }
fn main() {
let x = 22;
let f = &x;
impls_my_trait_val(f);
impls_my_trait::<&'static i32>();
random_where_clause();
}
// ferrocene-annotations: fls_fk2m2irwpeof
// Implementations
//
// ferrocene-annotations: fls_9i5msiuuyihf
// Paths
//
// ferrocene-annotations: fls_85vx1qfa061i
// Traits
//
// ferrocene-annotations: fls_151r19d7xbgz
// Entities
//
// ferrocene-annotations: fls_izl8iuhoz9e0
// Scopes
//
// ferrocene-annotations: fls_6ozthochxz1i
// Binding Scopes
//
// ferrocene-annotations: fls_ftphlagzd2te
// Generic Parameter Scope
//
// ferrocene-annotations: fls_m0z7omni9hp0
// Item Scope
//
// ferrocene-annotations: fls_769b4p8v3cwu
// Label Scope
//
// ferrocene-annotations: fls_kgbi26212eof
// Self Scope
//
// ferrocene-annotations: fls_octf6sf7yso
// Textual Macro Scope
//
// ferrocene-annotations: fls_lnpyb285qdiy
// Scope Hierarchy
//
// ferrocene-annotations: fls_dq403wq5yrs
// Namespaces
//
// ferrocene-annotations: fls_ld0ize96cm6m
// Preludes
//
// ferrocene-annotations: fls_ydmnb7qnmzzq
// Shadowing
//
// ferrocene-annotations: fls_40xoego2thsp
// Resolution
//
// ferrocene-annotations: fls_i6qzga6dyaee
// Path Resolution
//
// ferrocene-annotations: fls_o9u2h5m17kpz
// Path Expression Resolution