How to wait for a list of async function calls in rust?

Question

I have a list of async functions that I want to execute concurrently and then wait for all them to finish. The working code I have right now is:

async fn start_consumers(&self) {
    for consumer in &self.consumers {
        consumer.consume().await;
    }
}

This is not quite accurate as the functions are executed serially. I am looking for something like join!, but which works on a dynamic vector. With that I should be able to write something like:

async fn start_consumers(&self) {
    let mut v = Vec::new();
    for consumer in &self.consumers {
        consumer.consume();
    }
    join!(v);
}

Right now join! supports only tuples. I am looking for an alternative for that. Something similar to Promise.all() in JavaScript.

Answer 1

The futures crate has a join_all function which allows for waiting on a collection of futures:

use futures::future::join_all;

async fn start_consumers(&self) {
    let mut v = Vec::new();
    for consumer in &self.consumers {
        v.push(consumer.consume());
    }
    join_all(v).await;
 }

Answer 2

I also asked a similar question on the same day, but in my case I had a Result wrapped in a Future. So instead of join_all I had to use try_join_all