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//@ revisions: current next
//@[next] compile-flags: -Znext-solver
//@[current] run-pass
trait Get {
fn get(&mut self) -> u32;
}
impl Get for () {
fn get(&mut self) -> u32 {
0
}
}
impl<T> Get for &mut T
where
T: Get,
{
fn get(&mut self) -> u32 {
T::get(self) + 1
}
}
fn foo(n: usize, m: &mut ()) -> impl Get + use<'_> {
if n > 0 {
let mut iter = foo(n - 1, m);
//[next]~^ type annotations needed
assert_eq!(iter.get(), 1);
}
m
}
fn main() {
let g = foo(1, &mut ()).get();
assert_eq!(g, 1);
}
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