File: variance-use-invariant-struct-1.rs

package info (click to toggle)
rustc 1.88.0%2Bdfsg1-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 934,128 kB
  • sloc: xml: 158,127; python: 36,062; javascript: 19,855; sh: 19,700; cpp: 18,947; ansic: 12,993; asm: 4,792; makefile: 690; lisp: 29; perl: 29; ruby: 19; sql: 11
file content (23 lines) | stat: -rw-r--r-- 507 bytes parent folder | download | duplicates (18) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
 
// Test various uses of structs with distinct variances to make sure
// they permit lifetimes to be approximated as expected.

struct SomeStruct<T>(*mut T);

fn foo<'min,'max>(v: SomeStruct<&'max ()>)
                  -> SomeStruct<&'min ()>
    where 'max : 'min
{
    v
    //~^ ERROR lifetime may not live long enough
}

fn bar<'min,'max>(v: SomeStruct<&'min ()>)
                  -> SomeStruct<&'max ()>
    where 'max : 'min
{
    v
    //~^ ERROR lifetime may not live long enough
}


fn main() { }