On 09/29/2010 08:50 PM, Raymond Hettinger wrote:
1. Liberalize setobject.c binary operator methods to accept anything
registered to the Set ABC and add a backwards incompatible restriction
to the Set ABC binary operator methods to only accept Set ABC
instances (they currently accept any iterable).
This approach has a backwards incompatible tightening of the Set ABC,
but that will probably affect very few people. It also has the
disadvantage of not providing a straight-forward way to handle general
iterable arguments (either the implementer needs to write named binary
methods like update, difference, etc for that purpose or the user will
need to cast the the iterable to a set before operating on it). The
positive side of this option is that keeps the current advantages of
the setobject API and its NotImplemented return value.
1a. Liberalize setobject.c binary operator methods, restrict SetABC
methods, and add named methods (like difference, update, etc) that
accept any iterable.
I prefer 1 to 1a, but either is acceptable. 1 just forces you to call
set() on your iterable before operating on it, which I think helps
("explicit is better than implicit").
In 1a, by "add named methods that accept any iterable", you mean add
those to the SetABC? If so, then I'm more strongly for 1 and against
1a. I'm not convinced all classes implementing the Set ABC should have
to implement all those methods.
/larry/
_______________________________________________
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
