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//@ check-pass
//@ edition: 2021
use std::future::Future;
use std::pin::Pin;
use std::{marker::PhantomData, sync::Mutex};
type BoxFuture<'a, T> = Pin<Box<dyn Future<Output = T> + Send + 'a>>;
pub struct Scope<'scope, 'env: 'scope> {
enqueued: Mutex<Vec<BoxFuture<'scope, ()>>>,
phantom: PhantomData<&'env ()>,
}
impl<'scope, 'env: 'scope> Scope<'scope, 'env> {
pub fn spawn(&'scope self, future: impl Future<Output = ()> + Send + 'scope) {
self.enqueued.lock().unwrap().push(Box::pin(future));
}
}
fn scope_with_closure<'env, B>(_body: B) -> BoxFuture<'env, ()>
where
for<'scope> B: AsyncFnOnce(&'scope Scope<'scope, 'env>),
{
todo!()
}
type ScopeRef<'scope, 'env> = &'scope Scope<'scope, 'env>;
async fn go<'a>(value: &'a i32) {
let closure = async |scope: ScopeRef<'_, 'a>| {
let _future1 = scope.spawn(async {
// Make sure that `*value` is immutably borrowed with lifetime of
// `'a` and not with the lifetime of the containing coroutine-closure.
let _v = *value;
});
};
scope_with_closure(closure).await;
}
fn main() {}
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