Re: [Python-checkins] python/dist/src/Python compile.c, 2.340, 2.341
mwh at python.net
Thu Feb 10 00:22:59 CET 2005
rhettinger at users.sourceforge.net writes:
> Update of /cvsroot/python/python/dist/src/Python
> In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv26507/Python
> Modified Files:
> Log Message:
> Transform "x in (1,2,3)" to "x in frozenset([1,2,3])".
> Inspired by Skip's idea to recognize the throw-away nature of sequences
> in this context and to transform their type to one with better performance.
This breaks code:
>>>  in (1,)
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: list objects are unhashable
(and so breaks test_email -- is noone else running the test suite?).
It's a cute idea, but IMHO violates the principle of least surprise
ZAPHOD: Who are you?
ROOSTA: A friend.
ZAPHOD: Oh yeah? Anyone's friend in particular, or just generally
well-disposed to people? -- HHGttG, Episode 7
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