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//@ build-pass
// Ensures that we don't regress on "implementation is not general enough" when
// normalizating under binders. Unlike `normalization-generality.rs`, this also produces
// type outlives predicates that we must ignore.
pub unsafe trait Yokeable<'a> {
type Output: 'a;
}
pub struct Yoke<Y: for<'a> Yokeable<'a>> {
_marker: std::marker::PhantomData<Y>,
}
impl<Y: for<'a> Yokeable<'a>> Yoke<Y> {
pub fn project<P>(
&self,
_f: for<'a> fn(&<Y as Yokeable<'a>>::Output, &'a ()) -> <P as Yokeable<'a>>::Output,
) -> Yoke<P>
where
P: for<'a> Yokeable<'a>,
{
unimplemented!()
}
}
pub fn slice(y: Yoke<&'static str>) -> Yoke<&'static [u8]> {
y.project(move |yk, _| yk.as_bytes())
}
unsafe impl<'a, T: 'static + ?Sized> Yokeable<'a> for &'static T {
type Output = &'a T;
}
fn main() {}
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