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// This is a regression test for issue #114221.
// Check that we compute variances for lazy type aliases.
//@ check-pass
#![feature(lazy_type_alias)]
#![allow(incomplete_features)]
// [+] `A` is covariant over `'a`.
struct A<'a>(Co<'a>);
// [+] `Co` is covariant over `'a`.
type Co<'a> = &'a ();
fn co<'a>(x: A<'static>) {
let _: A<'a> = x;
}
// [-] `B` is contravariant over `'a`.
struct B<'a>(Contra<'a>);
// [-] `Contra` is contravariant over `'a`.
type Contra<'a> = fn(&'a ());
fn contra<'a>(x: B<'a>) {
let _: B<'static> = x;
}
struct C<T, U>(CoContra<T, U>);
// [+, -] `CoContra` is covariant over `T` and contravariant over `U`.
type CoContra<T, U> = Option<(T, fn(U))>;
fn co_contra<'a>(x: C<&'static (), &'a ()>) -> C<&'a (), &'static ()> {
x
}
fn main() {}
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