[Python-Dev] Stackless Design Q. (original) (raw)

Greg Ewing greg@cosc.canterbury.ac.nz
Wed, 20 Feb 2002 16:01:34 +1300 (NZDT)

Now I am at the point where I'm worst suited for: Design an interface.

Please tell me what you think, and what you'd like to change.

It's not clear exactly what you're after here. Are you trying to define the lowest-level interface upon which everything else will be built? If so, I think what you have presented is FAR too complex.

It seems to me you need only two things:

(1) A constructor for new tasklets:

t = tasklet(f)

  Takes a callable object f of no parameters and returns
  a tasklet which will execute the code of f. The tasklet
  is initially suspended and does not execute any of f's
  code until it is switched to for the first time.

(2) A way of switching to another tasklet:

t.transfer()

  Suspends the currently-running tasklet and resumes
  tasklet t were it last left off. This will either be
  at the beginning or where it last called the transfer()
  of another tasklet.

All the other stuff you talk about -- passing values between tasklets, rings of runnable tasklets, scheduling policies, etc -- can all be implemented in Python on top of these primitives.

Greg Ewing, Computer Science Dept, +--------------------------------------+ University of Canterbury, | A citizen of NewZealandCorp, a | Christchurch, New Zealand | wholly-owned subsidiary of USA Inc. | greg@cosc.canterbury.ac.nz +--------------------------------------+