Closing Channels in ActionScript

import flash.events.Event;
import flash.utils.setTimeout;

public class ClosingChannels extends Sprite {
    private var jobs:Array = [];
    private var done:Boolean = false;

    public function ClosingChannels() {
        addEventListener(Event.ADDED_TO_STAGE, onAdded);
    }

    private function onAdded(event:Event):void {
        startWorker();
        sendJobs();
    }

    private function startWorker():void {
        var worker:Function = function():void {
            if (jobs.length > 0) {
                var j:int = jobs.shift();
                trace("received job", j);
                setTimeout(worker, 0);
            } else if (!done) {
                setTimeout(worker, 0);
            } else {
                trace("received all jobs");
                checkForMoreJobs();
            }
        };
        setTimeout(worker, 0);
    }

    private function sendJobs():void {
        for (var j:int = 1; j <= 3; j++) {
            jobs.push(j);
            trace("sent job", j);
        }
        trace("sent all jobs");
        done = true;
    }

    private function checkForMoreJobs():void {
        var moreJobs:Boolean = jobs.length > 0;
        trace("received more jobs:", moreJobs);
    }
}

In this ActionScript example, we simulate the concept of closing channels and communicating between different parts of the program. Here’s how it works:

1. We create an array jobs to simulate a channel, and a boolean done to indicate when all jobs have been sent.

2. The startWorker function simulates a worker that continuously processes jobs. It uses setTimeout with a delay of 0 to simulate asynchronous behavior similar to goroutines.

3. The worker function checks if there are jobs in the array. If there are, it processes them. If not, it checks if done is true. If done is true and there are no more jobs, it finishes.

4. The sendJobs function sends 3 jobs by adding them to the jobs array, then sets done to true to indicate all jobs have been sent.

5. After all jobs are processed, checkForMoreJobs is called to check if there are any more jobs in the array, similar to checking a closed channel in the original example.

To run this program, you would typically compile it into a SWF file and run it in a Flash player or AIR runtime environment. The output would be similar to the original, showing jobs being sent and received, and finally checking if there are more jobs.

This ActionScript version doesn’t have built-in channel closing or synchronization primitives like Go, so we simulate these concepts using arrays and boolean flags. The asynchronous nature is simulated using setTimeout, which allows other code to run between job processing, similar to how goroutines work in Go.