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#![recursion_limit = "5"] // To reduce noise
//expect incompatible type error when ambiguous traits are in scope
//and not an overflow error on the span in the main function.
struct Ratio<T>(T);
pub trait Pow {
fn pow(self) -> Self;
}
impl<'a, T> Pow for &'a Ratio<T>
where
&'a T: Pow,
{
fn pow(self) -> Self {
self
}
}
fn downcast<'a, W: ?Sized>() -> std::io::Result<&'a W> {
todo!()
}
struct Other;
fn main() -> std::io::Result<()> {
let other: Other = downcast()?;//~ERROR 28:24: 28:35: `?` operator has incompatible types
Ok(())
}
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