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+/// !example
+/// ## Sending events both ways between the main thread and a worker thread
+/// 
+/// This third example demonstrates how we can use events to communicate in both directions
+/// between main thread and worker thread.
+/// 
+/// Like before, we create a worker thread and we define the fibonacci function:
+var Threads = require('webworker-threads');
+var t = Threads.create();
+
+function fibo(n) {
+	return n > 1 ? fibo(n - 1) + fibo(n - 2) : 1;
+}
+/// In the previous example we were running a loop that generates fibonacci numbers in the worker thread.  
+/// This is fine if the generator produces the number at a slower rate than the main thread can consume them 
+/// but it will hog memory if the main thread is too busy and cannot consume the data events fast enough.  
+/// We can improve this by controlling the flow with events in both directions.
+/// 
+/// The `thread` global variable that **webworker-threads** predefines in every worker thread is also an `EventEmitter`.  
+/// So we will use it to send events in the other direction, from the main thread to the worker thread.
+/// 
+/// Our modified generator does not use a loop any more. Instead, it generates numbers in response to `next` events
+/// sent from the main thread. Here is the new generator:
+function generateFibos() {
+	var i = 1;
+	thread.on('next', function() {
+		thread.emit('data', i, fibo(i));
+		i++;
+	});
+}
+/// From the main thread, we listen for the `data` events emitted by the worker thread.  
+/// Every time we get a `data` event from the worker thread, we print the result and we `emit` a 
+/// `next` event into the worker thread (stopping at 40): 
+t.on('data', function(n, result) {
+	console.log('fibo(' + n + ') = ' + result);
+	if (n < 40) t.emit('next');
+	else console.log('bye!'), t.destroy();
+});
+/// We now have all we need for our little ping-pong game. We load the two functions into the thread:
+t.eval(fibo);
+t.eval(generateFibos);
+/// We start the generator in the worker thread:
+t.eval("generateFibos()");
+/// And we start the game by emitting the first `next` event:
+t.emit('next');
+/// ### Output
+/// 
+/// ```
+/// fibo(1) = 1
+/// fibo(2) = 2
+/// fibo(3) = 3
+/// fibo(4) = 5
+/// ...
+/// fibo(39) = 102334155
+/// fibo(40) = 165580141
+/// bye!
+/// ```
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