#[allow(clippy::unnecessary_operation)] #[allow(clippy::implicit_clone)] fn main() { let x = &Baz; let y = &Baz; y.to_owned() == *x; let x = &&Baz; let y = &Baz; y.to_owned() == **x; } struct Foo; impl PartialEq for Foo { fn eq(&self, other: &Self) -> bool { self.to_owned() == *other } } impl ToOwned for Foo { type Owned = Bar; fn to_owned(&self) -> Bar { Bar } } #[derive(PartialEq, Eq)] struct Baz; impl ToOwned for Baz { type Owned = Baz; fn to_owned(&self) -> Baz { Baz } } #[derive(PartialEq, Eq)] struct Bar; impl PartialEq for Bar { fn eq(&self, _: &Foo) -> bool { true } } impl std::borrow::Borrow for Bar { fn borrow(&self) -> &Foo { static FOO: Foo = Foo; &FOO } }