[issue30932] Identity comparison ("is") fails for floats in Python3 but works in Python2

[Steven D'Aprano]

Steven D'Aprano added the comment:

This is not a bug. Whether Python allocates one, or two, float objects for a particular floating point value is dependent on the implementation and not a language guarantee. The language does not promise that two floats with the value 7.3 will be the same object, only that they are equal.

In Python 3.5 on Linux, I can see:

py> 7.3 is 7.3
True
py> x = 7.3
py> y = 7.3
py> x is y
False


*but your results may be different*. There is no language promise here, except that `x is x` must be true.

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nosy: +steven.daprano
resolution:  -> not a bug
stage:  -> resolved
status: open -> closed

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue30932>
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