[Python-Dev] pending deprecation warning for Set.update

[Jeremy Hylton]

It looks like current CVS has grown a pending deprecation warning for
the update() method of Sets and that this change has been backported to
the 2.3 branch.  It seems to me to be bad form to add a warning in a
maintenance release.  The update() method was new in 2.3 and documented
in the 2.3 docs.  So people are going to write code using update() and
then update to 2.3.1 and get warnings?

I'm also not clear on the rationale for the warning.  update() seems to
match the semantics of dict.update(), and it less verbose than the
suggested alternative -- union_update().

Jeremy