See this mailing-list discussion.
As @StefanKarpinski notes, the combinations function should really return an Iterator type; the task-based interface was doubtless easier to implement but is harder to use.
Furthermore, it looks like we have a little ways to go in order to beat the CPython itertools.combinations function.
The partitions function should likewise be improved. We probably want iterable permutations and subsets functions as well.
Combinations iterator, for #3989
based on code by @kmsquire
Now we are significantly faster.
Nice! But a hornéd hat of shame for not updating the documentation...
drat. thanks for the reminder.
Is this now done? Can we close the issue and add a NEWS item?
The integer and set partitions functions haven't been converted yet.
I should be submittiing these in a few minutes.
Kevin you're a beast!