[Python-ideas] Implement __add__ for set and frozenset

[Arnaud Delobelle]

2008/6/4 Raymond Hettinger <python at rcn.com>:
> In the case of intersection and intersection_update, if the inputs are sets
> or dicts, then they should be processed smallest to largest.  If the inputs
> are not sets or dicts, then process them in input order.

That means sorting the inputs by size, doesn't it?  Looking at
PyList_Sort, it doesn't let you provide a key, that means explicit
DSU.  Or is there another way?

-- 
Arnaud