On 4/22/2015 8:45 PM, Guido van Rossum wrote:
On Wed, Apr 22, 2015 at 2:38 PM, Chris Barker <chris.bar...@noaa.gov <mailto:chris.bar...@noaa.gov>> wrote:
On Tue, Apr 21, 2015 at 11:32 PM, Terry Reedy <tjre...@udel.edu <mailto:tjre...@udel.edu>> wrote: I was just thinking today that for this, typing needs a subtraction (difference) operation in addition to an addition (union) operation: Difference(Iterable(str), str)
Anyway, the point is that being able to say "all these types, except this one" would solve this particular problem -- but would it solve any others? Do we want this to work around a quirk in Pythons string type?
More seriously, I doubt there are other important use cases for Difference.
I thought about Difference(numbers.Number, complex) to get ordered numbers, but numbers.Real should probably work. I agree more real uses are needed before adding Difference.
-- Terry Jan Reedy _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com