On 5/09/12 15:19:47, Franck Ditter wrote: > Thanks to all, but : > - I should have said that I work with Python 3. Does that matter ? > - May I reformulate the queston : "a is b" and "id(a) == id(b)" > both mean : "a et b share the same physical address". Is that True ?
Yes. Keep in mind, though, that in some implementation (e.g. Jython), the physical address may change during the life time of an object. It's usually phrased as "a and b are the same object". If the object is mutable, then changing a will also change b. If a and b aren't mutable, then it doesn't really matter whether they share a physical address. Keep in mind that physical addresses can be reused when an object is destroyed. For example, in my Python3, id(math.sqrt(17)) == id(math.cos(17)) returns True, even though the floats involved are different, because the flaots have non-overlapping lifetimes and the physical address happens to be reused. Hope this helps, -- HansM -- http://mail.python.org/mailman/listinfo/python-list
