Await list of async predicates, but drop out on first false

Question

Imagine the following class:

public class Checker
{
   public async Task Check() { ... }
}

Now, imagine a list of instances of

Answer 1

And how can I shortcut the enumeration as soon as a checker returns false?

This will check the tasks' result in order of completion. So if task #5 is the first to complete, and returns false, the method returns false immediately, regardless of the other tasks. Slower tasks (#1, #2, etc) would never be checked.

public static async Task AllAsync(this IEnumerable> source)
{
    var tasks = source.ToList();

    while(tasks.Count != 0)
    {
        var finishedTask = await Task.WhenAny(tasks);

        if(! finishedTask.Result)
            return false;

        tasks.Remove(finishedTask);
    }

    return true;
}

Usage:

bool result = await checkers.Select(c => c.Check())
                            .AllAsync();