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| References | (1 earlier) <4f101f45$0$29999$c3e8da3$5496439d@news.astraweb.com> <mailman.4712.1326457859.27778.python-list@python.org> <4f102bd0$0$29999$c3e8da3$5496439d@news.astraweb.com> <4F107AAF.5000600@stoneleaf.us> <20120202141812.649c31d832bb15bd899eb952@johnohagan.com> |
|---|---|
| From | Devin Jeanpierre <jeanpierreda@gmail.com> |
| Date | 2012-02-02 01:34 -0500 |
| Subject | Re: copy on write |
| Newsgroups | comp.lang.python |
| Message-ID | <mailman.5343.1328164533.27778.python-list@python.org> (permalink) |
On Wed, Feb 1, 2012 at 10:18 PM, John O'Hagan <research@johnohagan.com> wrote:
> On Fri, 13 Jan 2012 10:40:47 -0800
> Ethan Furman <ethan@stoneleaf.us> wrote:
>
>> Steven D'Aprano wrote:
>> > Normally this is harmless, but there is one interesting little
>> > glitch you can get:
>> >
>> >>>> t = ('a', [23])
>> >>>> t[1] += [42]
>> > Traceback (most recent call last):
>> > File "<stdin>", line 1, in <module>
>> > TypeError: 'tuple' object does not support item assignment
>> >>>> t
>> > ('a', [23, 42])
>
> IMHO, this is worthy of bug-hood: shouldn't we be able to conclude from the TypeError that the assignment failed?
It did fail. The mutation did not.
I can't think of any way out of this misleadingness, although if you
can that would be pretty awesome.
-- Devin
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copy on write Eduardo Suarez-Santana <esuarez@itccanarias.org> - 2012-01-13 11:33 +0000
Re: copy on write Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-13 12:10 +0000
Re: copy on write Chris Angelico <rosuav@gmail.com> - 2012-01-13 23:30 +1100
Re: copy on write Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-13 13:04 +0000
Re: copy on write Ethan Furman <ethan@stoneleaf.us> - 2012-01-13 10:40 -0800
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-13 14:26 -0800
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-13 14:26 -0800
Re: copy on write John O'Hagan <research@johnohagan.com> - 2012-02-02 14:18 +1100
Re: copy on write Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-02-02 01:34 -0500
Re: copy on write John O'Hagan <research@johnohagan.com> - 2012-02-02 19:11 +1100
Re: copy on write Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-02 09:16 +0000
Re: copy on write Hrvoje Niksic <hniksic@xemacs.org> - 2012-02-02 11:53 +0100
Re: copy on write MRAB <python@mrabarnett.plus.com> - 2012-02-02 16:28 +0000
Re: copy on write Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-02-02 12:21 -0500
Re: copy on write John O'Hagan <research@johnohagan.com> - 2012-02-03 01:17 +1100
Re: copy on write Terry Reedy <tjreedy@udel.edu> - 2012-02-02 12:25 -0500
Re: copy on write John O'Hagan <research@johnohagan.com> - 2012-02-03 14:08 +1100
Re: copy on write Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-03 05:04 +0000
Re: copy on write Chris Angelico <rosuav@gmail.com> - 2012-02-03 16:28 +1100
Re: copy on write Rick Johnson <rantingrickjohnson@gmail.com> - 2012-02-03 07:35 -0800
Re: copy on write Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2012-02-03 10:08 +0100
Re: copy on write John O'Hagan <research@johnohagan.com> - 2012-02-03 21:47 +1100
Re: copy on write Wolfram Hinderer <wolfram.hinderer@googlemail.com> - 2012-02-05 06:09 -0800
Re: copy on write "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2012-02-03 16:15 +0000
Re: copy on write Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-02-02 11:42 +0100
Re: copy on write Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-01-13 08:50 -0500
Re: copy on write Grant Edwards <invalid@invalid.invalid> - 2012-01-13 15:13 +0000
Re: copy on write Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-01-13 11:48 -0500
Re: copy on write Neil Cerutti <neilc@norwich.edu> - 2012-01-13 16:54 +0000
Re: copy on write Grant Edwards <invalid@invalid.invalid> - 2012-01-13 18:15 +0000
Re: copy on write Chris Angelico <rosuav@gmail.com> - 2012-01-14 05:26 +1100
Re: copy on write Grant Edwards <invalid@invalid.invalid> - 2012-01-13 19:30 +0000
Re: copy on write Neil Cerutti <neilc@norwich.edu> - 2012-01-13 20:11 +0000
Re: copy on write Evan Driscoll <edriscoll@wisc.edu> - 2012-01-13 13:24 -0600
Re: copy on write Neil Cerutti <neilc@norwich.edu> - 2012-01-13 21:20 +0000
Re: copy on write Evan Driscoll <edriscoll@wisc.edu> - 2012-01-13 16:48 -0600
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-02-02 05:33 -0800
Re: copy on write Evan Driscoll <edriscoll@wisc.edu> - 2012-02-02 15:20 -0600
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-02-02 05:33 -0800
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-02-03 14:16 -0800
Re: copy on write 88888 Dihedral <dihedral88888@googlemail.com> - 2012-02-03 14:16 -0800
Re: copy on write Rick Johnson <rantingrickjohnson@gmail.com> - 2012-02-01 19:51 -0800
Re: copy on write Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-02 05:31 +0000
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