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//@ run-pass
// Regression test for issue #47139:
//
// Same as issue-47139-1.rs, but the impls of dummy are in the
// opposite order. This influenced the way that coherence ran and in
// some cases caused the overflow to occur when it wouldn't otherwise.
// In an effort to make the regr test more robust, I am including both
// orderings.
#![allow(dead_code)]
pub trait Insertable {
type Values;
fn values(self) -> Self::Values;
}
impl<T> Insertable for Option<T>
where
T: Insertable,
T::Values: Default,
{
type Values = T::Values;
fn values(self) -> Self::Values {
self.map(Insertable::values).unwrap_or_default()
}
}
impl<'a, T> Insertable for &'a Option<T>
where
Option<&'a T>: Insertable,
{
type Values = <Option<&'a T> as Insertable>::Values;
fn values(self) -> Self::Values {
self.as_ref().values()
}
}
impl<'a, T> Insertable for &'a [T]
{
type Values = Self;
fn values(self) -> Self::Values {
self
}
}
trait Unimplemented { }
trait Dummy { }
struct Foo<T> { t: T }
impl<T> Dummy for T
where T: Unimplemented
{ }
impl<'a, U> Dummy for Foo<&'a U>
where &'a U: Insertable
{
}
fn main() {
}
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