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| From | Peter Otten <__peter__@web.de> |
| Subject | Re: Tuples and immutability |
| Date | Fri, 07 Mar 2014 12:38:07 +0100 |
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Chris Angelico wrote:
> On Fri, Mar 7, 2014 at 8:33 PM, Duncan Booth
> <duncan.booth@invalid.invalid> wrote:
>> Is there any reason why tuples need to throw an exception on assigning to
>> the element if the old value and new value are the same object?
>
> It'd be easy enough to implement your own tuple subclass that behaves
> that way. Try it! See how many situations it actually helps.
>>> class T(tuple):
... def __setitem__(self, index, value):
... if value is not self[index]:
... raise TypeError("{} is not {}".format(value,
self[index]))
...
>>> for i, k in zip(range(250, 260), range(250, 260)):
... T([i])[0] = k
...
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
File "<stdin>", line 4, in __setitem__
TypeError: 257 is not 257
I'm not sure "help" is the right word here ;)
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Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-02-27 17:01 +0100
Re: Tuples and immutability Zachary Ware <zachary.ware+pylist@gmail.com> - 2014-02-27 10:13 -0600
Re: Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-02-27 17:27 +0100
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-02-28 03:33 +1100
Re: Tuples and immutability Zachary Ware <zachary.ware+pylist@gmail.com> - 2014-02-27 10:47 -0600
Re: Tuples and immutability Nick Timkovich <prometheus235@gmail.com> - 2014-02-27 15:47 -0600
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-02-28 08:52 +1100
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-02-27 15:18 -0700
Re: Tuples and immutability Rick Johnson <rantingrickjohnson@gmail.com> - 2014-03-11 19:01 -0700
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-12 13:10 +1100
Re: Tuples and immutability Terry Reedy <tjreedy@udel.edu> - 2014-03-11 23:25 -0400
Re: Tuples and immutability Steven D'Aprano <steve@pearwood.info> - 2014-03-12 06:28 +0000
Re: Tuples and immutability Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2014-03-12 10:39 +0100
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-12 03:40 -0600
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-12 03:51 -0600
Re: Tuples and immutability Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2014-03-12 12:21 +0100
Re: Tuples and immutability Ethan Furman <ethan@stoneleaf.us> - 2014-03-11 23:32 -0700
Re: Tuples and immutability Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2014-03-12 10:20 +0000
Re: Tuples and immutability Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2014-03-01 18:55 +0000
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-02-28 03:14 +1100
Re: Tuples and immutability Marko Rauhamaa <marko@pacujo.net> - 2014-02-27 18:19 +0200
Re: Tuples and immutability John O'Hagan <research@johnohagan.com> - 2014-02-28 16:17 +1100
Re: Tuples and immutability Marko Rauhamaa <marko@pacujo.net> - 2014-02-28 09:54 +0200
Re: Tuples and immutability Joshua Landau <joshua@landau.ws> - 2014-02-28 14:41 +0000
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-01 01:43 +1100
Re: Tuples and immutability Duncan Booth <duncan.booth@invalid.invalid> - 2014-03-07 09:33 +0000
Re: Tuples and immutability Ben Finney <ben+python@benfinney.id.au> - 2014-03-07 22:04 +1100
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-07 22:11 +1100
Re: Tuples and immutability Peter Otten <__peter__@web.de> - 2014-03-07 12:38 +0100
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-07 22:45 +1100
Re: Tuples and immutability Alister <alister.ware@ntlworld.com> - 2014-03-07 11:51 +0000
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-07 11:23 -0700
Re: Tuples and immutability Roy Smith <roy@panix.com> - 2014-03-07 08:37 -0500
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-08 15:17 +1300
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-07 21:17 -0700
Balanced trees (was: Re: Tuples and immutability) Marko Rauhamaa <marko@pacujo.net> - 2014-03-08 10:34 +0200
Re: Balanced trees (was: Re: Tuples and immutability) Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-08 04:03 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-08 13:26 +0200
Re: Balanced trees (was: Re: Tuples and immutability) Dan Stromberg <drsalists@gmail.com> - 2014-03-08 11:58 -0800
Re: Balanced trees Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-08 20:37 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-08 23:21 +0200
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-08 17:22 -0500
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-09 11:17 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-08 17:31 -0800
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-09 11:27 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-09 14:20 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-09 23:32 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-09 14:37 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-09 23:43 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-09 15:08 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-10 00:24 +0200
Re: Balanced trees Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-09 18:04 -0600
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-10 03:24 +0000
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-10 03:24 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-10 08:16 +0200
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-10 08:53 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-10 11:41 +0200
Re: Balanced trees Ned Batchelder <ned@nedbatchelder.com> - 2014-03-10 06:57 -0400
Re: Balanced trees Rustom Mody <rustompmody@gmail.com> - 2014-03-10 09:01 -0700
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-11 02:02 +0000
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-10 22:20 -0400
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 13:29 +1100
Re: Balanced trees Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-10 09:51 +0000
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-10 09:59 -0400
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 03:20 +1100
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 03:24 +1100
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-10 19:08 +0200
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 04:17 +1100
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-10 19:34 +0200
Re: Balanced trees Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-13 12:40 -0600
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-13 23:57 +0000
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-13 20:12 -0700
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-14 05:02 +0000
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-10 19:24 -0400
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 10:27 +1100
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-11 01:26 +0000
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 12:45 +1100
Re: Balanced trees Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-10 21:38 -0600
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 15:28 +1100
Re: Balanced trees "Rhodri James" <rhodri@wildebst.org.uk> - 2014-03-12 00:57 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-11 12:12 +0200
Re: Balanced trees alex23 <wuwei23@gmail.com> - 2014-03-12 10:13 +1000
Re: Balanced trees Alister <alister.ware@ntlworld.com> - 2014-03-11 09:25 +0000
Re: Balanced trees Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2014-03-12 10:08 +0100
Re: Balanced trees Tim Chase <python.list@tim.thechases.com> - 2014-03-10 11:33 -0500
Re: Balanced trees Chris Angelico <rosuav@gmail.com> - 2014-03-11 03:39 +1100
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-10 18:05 -0700
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-10 22:13 -0400
Re: Balanced trees Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2014-03-10 19:57 -0400
Re: Balanced trees Joshua Landau <joshua@landau.ws> - 2014-03-15 01:13 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-18 00:05 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-18 12:26 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-18 22:55 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-18 14:45 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-19 00:03 +0200
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-18 15:21 -0700
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-19 01:11 +0200
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-19 01:15 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-19 10:49 +0200
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-19 13:42 +0000
Re: Balanced trees Marko Rauhamaa <marko@pacujo.net> - 2014-03-19 15:54 +0200
Re: Balanced trees Roy Smith <roy@panix.com> - 2014-03-19 10:06 -0400
Re: Balanced trees Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-19 01:15 +0000
Re: Balanced trees Ethan Furman <ethan@stoneleaf.us> - 2014-03-19 08:15 -0700
Re: Balanced trees "Rhodri James" <rhodri@wildebst.org.uk> - 2014-03-20 02:16 +0000
Re: Balanced trees Dan Stromberg <drsalists@gmail.com> - 2014-03-19 19:34 -0700
Re: Balanced trees Chris Kaynor <ckaynor@zindagigames.com> - 2014-03-18 18:02 -0700
Re: Balanced trees Daniel Stutzbach <stutzbach@google.com> - 2014-03-18 13:18 -0700
blist in standard library (was Re: Balanced trees) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-15 12:31 +0000
Re: Balanced trees Daniel Stutzbach <stutzbach@google.com> - 2014-03-17 14:16 -0700
Re: Balanced trees Joshua Landau <joshua@landau.ws> - 2014-03-18 00:08 +0000
Re: Balanced trees Daniel Stutzbach <stutzbach@google.com> - 2014-03-17 18:01 -0700
Re: Balanced trees Joshua Landau <joshua@landau.ws> - 2014-03-18 07:46 +0000
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-09 13:40 +1300
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-08 19:39 -0700
Re: Tuples and immutability Marko Rauhamaa <marko@pacujo.net> - 2014-03-09 11:35 +0200
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-10 11:03 +1300
Re: Tuples and immutability Terry Reedy <tjreedy@udel.edu> - 2014-03-09 19:00 -0400
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-09 17:42 -0600
Re: Tuples and immutability Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-10 02:37 +0000
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-10 02:35 -0600
Re: Tuples and immutability Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-10 09:13 +0000
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-11 18:15 +1300
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-11 18:03 +1300
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-11 04:39 -0600
Re: Tuples and immutability Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-11 16:46 +0000
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-12 10:23 +1300
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-11 17:06 -0600
Re: Tuples and immutability Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-12 23:20 +0000
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-12 19:35 -0600
Re: Tuples and immutability Terry Reedy <tjreedy@udel.edu> - 2014-03-12 22:09 -0400
Re: Tuples and immutability Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-09 13:45 +1300
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-08 19:55 -0700
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-02-28 16:22 -0800
Re: Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-03-01 02:27 +0100
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-02-28 20:45 -0800
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-02-28 22:34 -0700
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-02-28 21:50 -0800
Re: Tuples and immutability Ned Batchelder <ned@nedbatchelder.com> - 2014-03-01 12:56 -0500
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-02-28 22:26 -0700
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-01 12:39 +1100
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-02-28 22:16 -0700
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-02-28 22:16 -0800
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-01 17:29 +1100
Re: Tuples and immutability Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-01 14:54 +0000
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-03-01 13:01 -0800
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-02-28 22:25 -0800
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-01 12:45 -0700
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-03-01 13:21 -0800
Re: Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-03-02 03:04 +0100
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-03-01 18:28 -0800
Re: Tuples and immutability Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-02 05:32 -0700
Re: Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-03-02 14:38 +0100
Re: Tuples and immutability Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-02 14:05 +0000
Re: Tuples and immutability Eric Jacoboni <eric.jacoboni@gmail.com> - 2014-03-02 15:17 +0100
Re: Tuples and immutability "albert visser" <albert.visser@gmail.com> - 2014-03-02 15:37 +0100
Re: Tuples and immutability "Mark H. Harris" <harrismh777@gmail.com> - 2014-03-01 18:15 -0800
Re: Tuples and immutability Joshua Landau <joshua@landau.ws> - 2014-03-09 17:54 +0000
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-10 05:13 +1100
Re: Tuples and immutability Joshua Landau <joshua@landau.ws> - 2014-03-09 19:57 +0000
Re: Tuples and immutability Chris Angelico <rosuav@gmail.com> - 2014-03-10 07:06 +1100
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