blob: 67f56bcde939a69588bda927b205d25c1d78620f (
plain)
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
|
// check-pass
#![allow(dead_code)]
#![allow(unused_assignments)]
#![allow(unused_variables)]
#![feature(type_alias_impl_trait)]
fn main() {
assert_eq!(foo().to_string(), "foo");
assert_eq!(bar1().to_string(), "bar1");
assert_eq!(bar2().to_string(), "bar2");
let mut x = bar1();
x = bar2();
assert_eq!(my_iter(42u8).collect::<Vec<u8>>(), vec![42u8]);
}
use defining_use_scope::*;
mod defining_use_scope {
// single definition
pub type Foo = impl std::fmt::Display;
pub fn foo() -> Foo {
"foo"
}
// two definitions
pub type Bar = impl std::fmt::Display;
pub fn bar1() -> Bar {
"bar1"
}
pub fn bar2() -> Bar {
"bar2"
}
pub type MyIter<T> = impl Iterator<Item = T>;
pub fn my_iter<T>(t: T) -> MyIter<T> {
std::iter::once(t)
}
fn my_iter2<T>(t: T) -> MyIter<T> {
std::iter::once(t)
}
// param names should not have an effect!
fn my_iter3<U>(u: U) -> MyIter<U> {
std::iter::once(u)
}
// param position should not have an effect!
fn my_iter4<U, V>(_: U, v: V) -> MyIter<V> {
std::iter::once(v)
}
// param names should not have an effect!
type MyOtherIter<T> = impl Iterator<Item = T>;
fn my_other_iter<U>(u: U) -> MyOtherIter<U> {
std::iter::once(u)
}
trait Trait {}
type GenericBound<'a, T: Trait + 'a> = impl Sized + 'a;
fn generic_bound<'a, T: Trait + 'a>(t: T) -> GenericBound<'a, T> {
t
}
mod pass_through {
pub type Passthrough<T: 'static> = impl Sized + 'static;
fn define_passthrough<T: 'static>(t: T) -> Passthrough<T> {
t
}
}
fn use_passthrough(x: pass_through::Passthrough<u32>) -> pass_through::Passthrough<u32> {
x
}
}
|