File: hrtb-higher-ranker-supertraits.rs

package info (click to toggle)
rustc 1.89.0%2Bdfsg1-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 906,624 kB
  • sloc: xml: 158,148; python: 34,888; javascript: 19,595; sh: 19,221; ansic: 13,046; cpp: 7,144; asm: 4,376; makefile: 692; lisp: 174; sql: 15
file content (40 lines) | stat: -rw-r--r-- 978 bytes parent folder | download | duplicates (15)
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
// Test a trait (`Bar`) with a higher-ranked supertrait.
#![allow(unconditional_recursion)]

trait Foo<'tcx> {
    fn foo(&'tcx self) -> &'tcx isize;
}

trait Bar<'ccx>: for<'tcx> Foo<'tcx> {
    fn bar(&'ccx self) -> &'ccx isize;
}

fn want_foo_for_some_tcx<'x, F: Foo<'x>>(f: &'x F) {
    want_foo_for_some_tcx(f);
    want_foo_for_any_tcx(f);
    //~^ ERROR the trait bound `for<'tcx> F: Foo<'tcx>` is not satisfied
}

fn want_foo_for_any_tcx<F: for<'tcx> Foo<'tcx>>(f: &F) {
    want_foo_for_some_tcx(f);
    want_foo_for_any_tcx(f);
}

fn want_bar_for_some_ccx<'x, B: Bar<'x>>(b: &B) {
    want_foo_for_some_tcx(b);
    want_foo_for_any_tcx(b);

    want_bar_for_some_ccx(b);
    want_bar_for_any_ccx(b);
    //~^ ERROR the trait bound `for<'ccx> B: Bar<'ccx>` is not satisfied
}

fn want_bar_for_any_ccx<B: for<'ccx> Bar<'ccx>>(b: &B) {
    want_foo_for_some_tcx(b);
    want_foo_for_any_tcx(b);

    want_bar_for_some_ccx(b);
    want_bar_for_any_ccx(b);
}

fn main() {}