Here some ideas that have been proposed for sets: * New method (proposed by Shane Holloway): s1.isdisjoint(s2). Logically equivalent to "not s1.intersection(s2)" but has an early-out if a common member is found. The speed-up is potentially large given two big sets that may largely overlap or may not intersect at all. There is also a memory savings since a new set does not have to be formed and then thrown away.
* Additional optional arguments for basic set operations to allow chained operations. For example, s=s1.union(s2, s3, s4) would be logically equivalent to s=s1.union(s2).union(s3).union(s4) but would run faster because no intermediate sets are created, copied, and discarded. It would run as if written: s=s1.copy(); s.update(s2); s.update(s3); s.update(s4). * Make sets listenable for changes (proposed by Jason Wells): s = set(mydata) def callback(s): print 'Set %d now has %d items' % (id(s), len(s)) s.listeners.append(callback) s.add(existing_element) # no callback s.add(new_element) # callback Raymond _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com