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// check-pass
// [next] compile-flags: -Zlower-impl-trait-in-trait-to-assoc-ty
// revisions: current next
#![feature(return_position_impl_trait_in_trait)]
//~^ WARN the feature `return_position_impl_trait_in_trait` is incomplete
struct TestA {}
struct TestB {}
impl TestTrait for TestA {
type Output = ();
}
impl TestTrait for TestB {
type Output = ();
}
trait TestTrait {
type Output;
}
impl<A, B> TestTrait for GreeterOutput<A, B>
where
A: TestTrait<Output = ()>,
B: TestTrait<Output = ()>,
{
type Output = ();
}
enum GreeterOutput<A, B>
where
A: TestTrait<Output = ()>,
B: TestTrait<Output = ()>,
{
SayHello(A),
SayGoodbye(B),
}
trait Greeter {
fn test_func(&self, func: &str) -> impl TestTrait<Output = ()> {
match func {
"SayHello" => GreeterOutput::SayHello(TestA {}),
"SayGoodbye" => GreeterOutput::SayGoodbye(TestB {}),
_ => GreeterOutput::SayHello(TestA {}),
}
}
}
fn main() {
println!("Hello, world!");
}
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