Message 166009 - Python tracker

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In-reply-to
Author	sbt
Recipients	docs@python, pitrou, sbt
Date	2012年07月21日.10:58:21
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1342868302.42.0.824683171539.issue15412@psf.upfronthosting.co.za>

Content
> The weakref is "dead" but it's still a weakref, and it can be used to > e.g. index a container of existing weakrefs (cf. WeakSet, > WeakKeyDictionary, WeakValueDictionary). Ah. I had assumed that since dead weakrefs were unhashable you couldn't safely use them as keys in a dict. (Presumably removal of a no longer hashable key from a dict is O(n)?) I also hadn't realize that weakrefs were subclassable.

Content

> The weakref is "dead" but it's still a weakref, and it can be used to
> e.g. index a container of existing weakrefs (cf. WeakSet,
> WeakKeyDictionary, WeakValueDictionary).
Ah.
I had assumed that since dead weakrefs were unhashable you couldn't safely use them as keys in a dict. (Presumably removal of a no longer hashable key from a dict is O(n)?)
I also hadn't realize that weakrefs were subclassable.

History
Date	User	Action	Args
2012年07月21日 10:58:22	sbt	set	recipients: + sbt, pitrou, docs@python
2012年07月21日 10:58:22	sbt	set	messageid: <1342868302.42.0.824683171539.issue15412@psf.upfronthosting.co.za>
2012年07月21日 10:58:21	sbt	link	issue15412 messages
2012年07月21日 10:58:21	sbt	create

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