Miklos and Tom,
one option may be to merge the work that Miklos described with
gr-trellis
(or the other way around :-))
Recall there was a discussion in the recent past of volk-ing the basic
trellis algorithms such as VA and SISO.
I believe the work that Miklos describes would be a wonderful way to
start.
Also, Miklos, some of the functionality you are describing
(interleaving,
generation of codes, FSM structure, etc) is in gr-trellis.
In the spirit of not duplicating efforts, would you consider a joint
effort
to refactor as much as possible into one module/API?
best
Achilleas