Message 145516 - Python tracker

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In-reply-to
Author	rhettinger
Recipients	ezio.melotti, rhettinger
Date	2011年10月14日.14:00:39
SpamBayes Score	2.9496021e-09
Marked as misclassified	No
Message-id	<1318600840.5.0.71026498354.issue13177@psf.upfronthosting.co.za>

Content
This changes behavior so that hash() gets called twice for the key tuple, resulting in decreased performance. In an earlier version of the lru_cache before the "with lock" was introduced, the try/except form was more atomic. It also worked well with dict subclasses that use __missing__ (which is bypassed with the LBYL style of lookup). I'll look at this more shortly -- thanks for the links to the other tracker items.

Content

This changes behavior so that hash() gets called twice for the key tuple, resulting in decreased performance.
In an earlier version of the lru_cache before the "with lock" was introduced, the try/except form was more atomic. It also worked well with dict subclasses that use __missing__ (which is bypassed with the LBYL style of lookup).
I'll look at this more shortly -- thanks for the links to the other tracker items.

History
Date	User	Action	Args
2011年10月14日 14:00:40	rhettinger	set	recipients: + rhettinger, ezio.melotti
2011年10月14日 14:00:40	rhettinger	set	messageid: <1318600840.5.0.71026498354.issue13177@psf.upfronthosting.co.za>
2011年10月14日 14:00:39	rhettinger	link	issue13177 messages
2011年10月14日 14:00:39	rhettinger	create

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