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//@ ignore-pass
//@ build-pass
//@ edition:2021
use std::future::Future;
use std::pin::Pin;
type BoxFuture<T> = Pin<Box<dyn Future<Output = T>>>;
fn main() {
let _ = wrapper_call(handler);
}
async fn wrapper_call(handler: impl Handler) {
handler.call().await;
}
async fn handler() {
f(&()).await;
}
async fn f<'a>(db: impl Acquire<'a>) {
db.acquire().await;
}
trait Handler {
type Future: Future;
fn call(self) -> Self::Future;
}
impl<Fut, F> Handler for F
where
F: Fn() -> Fut,
Fut: Future,
{
type Future = Fut;
fn call(self) -> Self::Future {
loop {}
}
}
trait Acquire<'a> {
type Connection;
fn acquire(self) -> BoxFuture<Self::Connection>;
}
impl<'a> Acquire<'a> for &'a () {
type Connection = Self;
fn acquire(self) -> BoxFuture<Self> {
loop {}
}
}
|
