Re: Correct type for a simple "bag of attributes" namespace object

References	(2 earlier) <53dd0717$0$29973$c3e8da3$5496439d@news.astraweb.com> <mailman.12548.1407009552.18130.python-list@python.org> <70e5f2f1-661f-40f2-bb7a-76e569c4d092@googlegroups.com> <CALwzidmZMReJL-XqOuxj5Q7mQhVA29itGZdmGCT3-6B7eyO_Sg@mail.gmail.com> <lrk7li$6nb$1@ger.gmane.org>
Date	2014-08-03 02:17 -0700
From	Albert-Jan Roskam <fomcl@yahoo.com>
Subject	Re: Correct type for a simple "bag of attributes" namespace object
Newsgroups	comp.lang.python
Message-ID	<mailman.12572.1407057640.18130.python-list@python.org> (permalink)

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--- Original Message -----
> From: Terry Reedy <tjreedy@udel.edu>
> To: python-list@python.org
> Cc: 
> Sent: Sunday, August 3, 2014 4:43 AM
> Subject: Re: Correct type for a simple "bag of attributes" namespace object
> 
> On 8/2/2014 8:59 PM, Ian Kelly wrote:
>>  On Sat, Aug 2, 2014 at 2:46 PM, Mark Summerfield 
> <list@qtrac.plus.com> wrote:
>>>  On Saturday, 2 August 2014 20:58:59 UTC+1, Ben Finney  wrote:
>>>>  Steven D'Aprano writes:
>>>> 
>>>>>  If you need instances which carry state, then object is the 
> wrong
>>>>>  class.
>>> 
>>>  Fair enough.
>>> 
>>>>  Right. The 'types' module provides a SimpleNamespace class 
> for the
>>>>  common "bag of attributes" use case::
>>>> 
>>>>       >>> import types
>>>>       >>> foo = types.SimpleNamespace()
>>>>       >>> foo.x = 3
>>>>       >>> foo
>>>>       namespace(x=3)
>>> 
>>>  This is too much for children (& beginners).
>>> 
>>>  But perhaps what I should be asking for is for a new built-in that does 
> what types.SimpleNamespace() does, so that without any import you can write, 
> say,
>>> 
>>>  foo = namespace(a=1, b=2)
>>>  # or
>>>  bar = namespace()
>>>  bar.a = 1

I find the following obscure (to me at least) use of type() useful exactly for this "bag of attributes" use case:
>>> employee = type("Employee", (object,), {})
>>> employee.name = "John Doe"
>>> employee.position = "Python programmer"
>>> employee.name, employee.position, employee
('John Doe', 'Python programmer', <class '__main__.Employee'>)

>>> details = dict(name="John Doe", position="Python programmer")
>>> employee = type("Employee", (object,), details)
>>> employee.name, employee.position, employee
('John Doe', 'Python programmer', <class '__main__.Employee'>)


regards,
Albert-Jan

Thread

3 Suggestions to Make Python Easier For Children Mark Summerfield <list@qtrac.plus.com> - 2014-08-01 23:45 -0700
  Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-02 10:14 +0300
    Re: 3 Suggestions to Make Python Easier For Children Mark Summerfield <list@qtrac.plus.com> - 2014-08-02 00:38 -0700
      Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-02 11:03 +0300
        Re: 3 Suggestions to Make Python Easier For Children Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-03 02:00 +1000
          Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-02 20:07 +0300
            Re: 3 Suggestions to Make Python Easier For Children Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-02 18:29 +0100
              Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-02 21:33 +0300
    Re: 3 Suggestions to Make Python Easier For Children Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-03 01:43 +1000
      Correct type for a simple “bag of attributes” namespace object (was: 3 Suggestions to Make Python Easier For Children) Ben Finney <ben+python@benfinney.id.au> - 2014-08-03 05:58 +1000
        Re: Correct type for a simple "bag of attributes" namespace object (was: 3 Suggestions to Make Python Easier For Children) Mark Summerfield <list@qtrac.plus.com> - 2014-08-02 13:46 -0700
          Re: Correct type for a simple "bag of attributes" namespace object (was: 3 Suggestions to Make Python Easier For Children) Chris Angelico <rosuav@gmail.com> - 2014-08-03 07:05 +1000
          Re: Correct type for a simple "bag of attributes" namespace object Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-02 22:16 +0100
          Re: Correct type for a simple "bag of attributes" namespace object Chris Angelico <rosuav@gmail.com> - 2014-08-03 07:24 +1000
          Re: Correct type for a simple "bag of attributes" namespace object Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-02 22:23 +0100
          Re: Correct type for a simple "bag of attributes" namespace object (was: 3 Suggestions to Make Python Easier For Children) Devin Jeanpierre <jeanpierreda@gmail.com> - 2014-08-02 16:18 -0700
          Re: Correct type for a simple "bag of attributes" namespace object (was: 3 Suggestions to Make Python Easier For Children) Chris Angelico <rosuav@gmail.com> - 2014-08-03 09:27 +1000
          Re: Correct type for a simple "bag of attributes" namespace object (was: 3 Suggestions to Make Python Easier For Children) Ian Kelly <ian.g.kelly@gmail.com> - 2014-08-02 18:59 -0600
          Re: Correct type for a simple "bag of attributes" namespace object Terry Reedy <tjreedy@udel.edu> - 2014-08-02 22:40 -0400
          Re: Correct type for a simple "bag of attributes" namespace object Terry Reedy <tjreedy@udel.edu> - 2014-08-02 22:43 -0400
          Re: Correct type for a simple "bag of attributes" namespace object Albert-Jan Roskam <fomcl@yahoo.com> - 2014-08-03 02:17 -0700
          Re: Correct type for a simple "bag of attributes" namespace object Peter Otten <__peter__@web.de> - 2014-08-03 11:37 +0200
          Re: Correct type for a simple "bag of attributes" namespace object Albert-Jan Roskam <fomcl@yahoo.com> - 2014-08-03 03:51 -0700
          Re: Correct type for a simple "bag of attributes" namespace object Albert-Jan Roskam <fomcl@yahoo.com> - 2014-08-03 04:14 -0700
          Re: Correct type for a simple "bag of attributes" namespace object Peter Otten <__peter__@web.de> - 2014-08-03 13:23 +0200
            Re: Correct type for a simple "bag of attributes" namespace object Marko Rauhamaa <marko@pacujo.net> - 2014-08-03 17:51 +0300
              Re: Correct type for a simple "bag of attributes" namespace object Roy Smith <roy@panix.com> - 2014-08-03 11:09 -0400
                Re: Correct type for a simple "bag of attributes" namespace object Marko Rauhamaa <marko@pacujo.net> - 2014-08-03 18:52 +0300
              Re: Correct type for a simple "bag of attributes" namespace object Terry Reedy <tjreedy@udel.edu> - 2014-08-03 18:55 -0400
                Re: Correct type for a simple "bag of attributes" namespace object Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-04 11:19 +1000
                Re: Correct type for a simple "bag of attributes" namespace object Terry Reedy <tjreedy@udel.edu> - 2014-08-04 01:26 -0400
              Re: Correct type for a simple "bag of attributes" namespace object Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-04 10:13 +1000
                Re: Correct type for a simple "bag of attributes" namespace object Roy Smith <roy@panix.com> - 2014-08-03 20:59 -0400
                Re: Correct type for a simple "bag of attributes" namespace object Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-08-04 13:00 +1200
                Re: Correct type for a simple "bag of attributes" namespace object Marko Rauhamaa <marko@pacujo.net> - 2014-08-04 08:41 +0300
                Re: Correct type for a simple "bag of attributes" namespace object Ian Kelly <ian.g.kelly@gmail.com> - 2014-08-04 00:41 -0600
                Re: Correct type for a simple "bag of attributes" namespace object Marko Rauhamaa <marko@pacujo.net> - 2014-08-04 09:57 +0300
          Re: Correct type for a simple "bag of attributes" namespace object Akira Li <4kir4.1i@gmail.com> - 2014-08-03 18:22 +0400
      Re: Correct type for a simple “bag of attributes” namespace object Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-03 13:28 +0100
        Re: Correct type for a simple “bag of attributes” namespace object Roy Smith <roy@panix.com> - 2014-08-03 08:40 -0400
          Re: Correct type for a simple “bag of attributes” namespace object Chris Angelico <rosuav@gmail.com> - 2014-08-03 22:56 +1000
            Re: Correct type for a simple “bag of attributes” namespace object Roy Smith <roy@panix.com> - 2014-08-03 09:25 -0400
              Re: Correct type for a simple “bag of attributes” namespace object Chris Angelico <rosuav@gmail.com> - 2014-08-03 23:35 +1000
                Re: Correct type for a simple “bag of attributes” namespace object Roy Smith <roy@panix.com> - 2014-08-03 10:36 -0400
                Re: Correct type for a simple “bag of attributes” namespace object Chris Angelico <rosuav@gmail.com> - 2014-08-04 01:00 +1000
      Re: Correct type for a simple “bag of attributes” namespace object Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-03 18:38 +0100
        Re: Correct type for a simple “bag of attributes” namespace object Roy Smith <roy@panix.com> - 2014-08-03 13:44 -0400
  Re: 3 Suggestions to Make Python Easier For Children Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-02 08:46 +0100
    Re: 3 Suggestions to Make Python Easier For Children Mark Summerfield <list@qtrac.plus.com> - 2014-08-02 01:03 -0700
      Re: 3 Suggestions to Make Python Easier For Children Terry Reedy <tjreedy@udel.edu> - 2014-08-02 19:14 -0400
  Re: 3 Suggestions to Make Python Easier For Children Terry Reedy <tjreedy@udel.edu> - 2014-08-02 19:12 -0400
  Re: 3 Suggestions to Make Python Easier For Children Brian Blais <bblais@gmail.com> - 2014-08-05 07:36 -0400
    Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-05 15:04 +0300
      Re: 3 Suggestions to Make Python Easier For Children Skip Montanaro <skip@pobox.com> - 2014-08-05 07:31 -0500
        Re: 3 Suggestions to Make Python Easier For Children Marko Rauhamaa <marko@pacujo.net> - 2014-08-05 16:19 +0300
          Re: 3 Suggestions to Make Python Easier For Children MRAB <python@mrabarnett.plus.com> - 2014-08-05 15:11 +0100
          Re: 3 Suggestions to Make Python Easier For Children Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-06 02:14 +1000
      Re: 3 Suggestions to Make Python Easier For Children Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-05 22:43 +1000
        Re: 3 Suggestions to Make Python Easier For Children Chris Angelico <rosuav@gmail.com> - 2014-08-05 23:08 +1000
      Re: 3 Suggestions to Make Python Easier For Children Chris Angelico <rosuav@gmail.com> - 2014-08-05 23:00 +1000

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