AwaitGroup

An asynchronous implementation of a WaitGroup.

A WaitGroup waits for a collection of tasks to finish. The main task can create new workers and pass them to each of the tasks it wants to wait for. Then, each of the tasks calls done when finished. The main task can call await to block until all other tasks have finished.

```rust use awaitgroup::WaitGroup;

#[tokio::main] async fn main() { let wg = WaitGroup::new();

for _ in 0..5 {
    // Create a new worker.
    let worker = wg.worker();

    tokio::spawn(async {
        // Do some work...

        // This task is done all of its work.
        worker.done();
    });
}

// Block until all other tasks have finished their work.
wg.await;

} ```