std.parallelism: How to wait all tasks finished?

[Cooler]

I have several tasks. Each task may or may not create another 
task. What is the best way to wait until all tasks finished?

The code:

void procData(){
   if(...)
     taskPool.put(task(&procData));
}

void main(){
   taskPool.put(task(&procData));
   taskPool.put(task(&procData));
   ...
   taskPool.put(task(&procData));

   // Next line will block execution until all tasks already in 
queue finished.
   // Almost all what I need, but new tasks will not be started.
   taskPool.finish(true);
}