Returning a future from a closure

help
1

Any idea how can I achieve something like the following?

The compiler complains that tx doesn't live long enough, and rightly so. How can I return a future that captures the variables it needs?

use std::future::Future;

async fn register_callback<F>(f :impl Fn() -> F)
  where 
  F: Future + Send + 'static
{
    f().await;
}


#[tokio::main]
async fn main() {
    let (tx, _) = tokio::sync::mpsc::channel::<()>(1);
    register_callback(|| {
        tx.clone().send(())
    });
}

https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=efc41e0f468fb770fe1e26c15f8335ba

2

I think I did it. Thanks!

use std::future::Future;

async fn register_callback<F>(f :impl Fn() -> F)
  where 
  F: Future + Send + 'static
{
    f().await;
}


#[tokio::main]
async fn main() {
    let (tx, _) = tokio::sync::mpsc::channel::<()>(1);
    register_callback(|| {
        let x = tx.clone();
        async move {x.send(()).await.unwrap();}
    }).await;
}
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