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//@ check-pass
//@ compile-flags: -Znext-solver
trait Foo {
type Gat<'a>
where
Self: 'a;
fn bar(&self) -> Self::Gat<'_>;
}
enum Option<T> {
Some(T),
None,
}
impl<T> Option<T> {
fn as_ref(&self) -> Option<&T> {
match self {
Option::Some(t) => Option::Some(t),
Option::None => Option::None,
}
}
fn map<U>(self, f: impl FnOnce(T) -> U) -> Option<U> {
match self {
Option::Some(t) => Option::Some(f(t)),
Option::None => Option::None,
}
}
}
impl<T: Foo + 'static> Foo for Option<T> {
type Gat<'a> = Option<<T as Foo>::Gat<'a>> where Self: 'a;
fn bar(&self) -> Self::Gat<'_> {
self.as_ref().map(Foo::bar)
}
}
fn main() {}
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