Difference of hash and __hash__()

[Terry Reedy]

"Stefan Fleiter" <stefan.fleiter at web.de> wrote in message
news:bj2nv5$hna$1 at news.web.de...

> under Python 2.2.2:
>
>  >>> s = slice(None,5,None)
>  >>> hash(s)
> Traceback (most recent call last):
>    File "<stdin>", line 1, in ?
> TypeError: unhashable type
>  >>> s.__hash__()
> 136775584
>
> Can anybody explain this?

It looks like a bug.  Extended slices were added for use by Numerical
Python.  It may never have tried to hash them or only done so only
through the C equivavlent of s.__hash__.  Extended slicing of
sequences was, I believe, only added in 2.3.

TJR