Ethan Furman added the comment: Victor Stinner commented: ------------------------- > I never understood the difference between "long" (__int__ method) > and "index" (__index__ method). Is the difference on the behaviour > of floating point numbers?
__index__ was originally added so that non-int integers, such as NumPy's int16, int32, etc, integer types could be used as indices and slices. Now it means "if your type can produce a lossless integer, use __index__", which is why float and similar types don't define it. The current meaning is unfortunate in that it is possible to want a type that can be used as an index or slice but that is still not a number, and in fact won't be used as a number in any scenario _except_ bin(), hex(), and oct(). It seems to me that by having those three functions check that the argument is a number, and bailing if it is not, is a decent way to ensure consistency. One question I do have, since I don't have NumPy installed, is what happens with: --> "NumPy's int's work here? %x" % uint16(7) ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue19995> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
