Message 241317 - Python tracker

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In-reply-to
Author	wim.glenn
Recipients	docs@python, wim.glenn
Date	2015年04月17日.07:22:57
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1429255378.08.0.140067438597.issue23986@psf.upfronthosting.co.za>

Content
The comparisons section of the python 2 docs says: --- https://docs.python.org/2/reference/expressions.html#comparisons For the list and tuple types, x in y is true if and only if there exists an index i such that x == y[i] is true. --- But it's not strictly speaking correct. Simplest counter-example: x = float('nan') y = [x] The python 3 docs instead mention correct equivalent which is any(x is e or x == e for e in y)

Content

The comparisons section of the python 2 docs says:
--- 
https://docs.python.org/2/reference/expressions.html#comparisons
For the list and tuple types, x in y is true if and only if there exists an index i such that x == y[i] is true.
---
But it's not strictly speaking correct. Simplest counter-example:
x = float('nan')
y = [x]
The python 3 docs instead mention correct equivalent which is 
any(x is e or x == e for e in y)

History
Date	User	Action	Args
2015年04月17日 07:22:58	wim.glenn	set	recipients: + wim.glenn, docs@python
2015年04月17日 07:22:58	wim.glenn	set	messageid: <1429255378.08.0.140067438597.issue23986@psf.upfronthosting.co.za>
2015年04月17日 07:22:58	wim.glenn	link	issue23986 messages
2015年04月17日 07:22:57	wim.glenn	create

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