set update in 2.5

Duncan Smith buzzard at
Sun Jan 28 03:10:18 CET 2007

     In moving from 2.4 to 2.5 I find that some of my unit tests are now
failing.  I've worked out that the problem relates to the set update
method.  In 2.4 I could update a set with an iterable type derived from
dict as the argument.  I now find that the set is updated with the hash
values of the items in my iterable, rather than the items themselves.
Converting to a list first gets round the problem.

My iterable type has the same API as 'set' but requires items to have
hashable 'uid' attributes, so they can also be looked up by uid.  I hope
this, and the fact that this worked fine in 2.4 will be enough to track
down the issue without me having to paste reams of code (other than the
following, pasted from IDLE).  Any ideas?  Cheers.


>>> from graphItems import Node
>>> from keyed_sets import KeyedSet
>>> n = Node(1)
>>> n.uid
>>> k = KeyedSet([n])
>>> k
>>> type(iter(k).next())
<class 'graphItems.Node'>
>>> type(k[1])
<class 'graphItems.Node'>
>>> s = set()
>>> s.update(list(k))
>>> type(iter(s).next())
<class 'graphItems.Node'>
>>> s = set()
>>> s.update(k)
>>> type(iter(s).next())
<type 'int'>
>>> s = set()
>>> s.add(n)
>>> type(iter(s).next())
<class 'graphItems.Node'>
>>> hash(n)

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