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
|
// The regression test for #15031 to make sure destructuring trait
// reference work properly.
#![feature(box_patterns)]
trait T { fn foo(&self) {} }
impl T for isize {}
fn main() {
// For an expression of the form:
//
// let &...&x = &..&SomeTrait;
//
// Say we have n `&` at the left hand and m `&` right hand, then:
// if n < m, we are golden;
// if n == m, it's a derefing non-derefable type error;
// if n > m, it's a type mismatch error.
// n < m
let &x = &(&1isize as &dyn T);
let &x = &&(&1isize as &dyn T);
let &&x = &&(&1isize as &dyn T);
// n == m
let &x = &1isize as &dyn T; //~ ERROR type `&dyn T` cannot be dereferenced
let &&x = &(&1isize as &dyn T); //~ ERROR type `&dyn T` cannot be dereferenced
let box x = Box::new(1isize) as Box<dyn T>;
//~^ ERROR type `Box<dyn T>` cannot be dereferenced
// n > m
let &&x = &1isize as &dyn T;
//~^ ERROR mismatched types
//~| expected trait object `dyn T`
//~| found reference `&_`
let &&&x = &(&1isize as &dyn T);
//~^ ERROR mismatched types
//~| expected trait object `dyn T`
//~| found reference `&_`
let box box x = Box::new(1isize) as Box<dyn T>;
//~^ ERROR mismatched types
//~| expected trait object `dyn T`
//~| found struct `Box<_>`
}
|
