Tasklets

New in version 0.8: Tasklets were added in version 0.8, starting with the betas (named 0.7.9..)

A Tasklet is a light-weight task. It looks very similar to a Task except that it does not save its results to disk. Every time you need its output, it is recomputed. Other than that, you can pass it around, just like a Task.

They also get sometimes automatically generated.

Before Tasklets

Before Tasklets were a part of jug, often there was a need to write some connector Tasks:

  1. def select_first(t):
  2.     return t[0]
  4. result = Task(...)
  5. result0 = Task(select_first, result)
  7. next = Task(next_step,result0)

This obviously works, but it has two drawbacks:

  1. It is not natural Python
  2. It is space inefficient on disk. You are saving result and then result0.

With Tasklets

First version:

  1. def select_first(t):
  2.     return t[0]
  3. result = Task(...)
  4. result0 = Tasklet(result, select_first)
  5. next = Task(next_step,result0)

If you look closely, you will see that we are now using a Tasklet. This jugfile will work exactly the same, but it will not save the result0 to disk. So you have a performance gain.

It is still not natural Python. However, the Task can generate Tasklets automatically:

Second version:

  1. result = Task(...)
  2. next = Task(next_function, result[0])

Now, we have a version that is both idiomatic Python and efficient.