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Re: Namespaces are one honking great idea

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From Ethan Furman <ethan@stoneleaf.us>
Newsgroups comp.lang.python
Subject Re: Namespaces are one honking great idea
Date Sat, 02 Jul 2016 22:14:37 -0700
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On 07/02/2016 08:44 PM, Steven D'Aprano wrote:

> Try getting this behaviour from within a class:
>
>
> class Food(metaclass=Namespace):
>
>      # (1) no special decorators required
>      def spam(n):
>          return ' '.join(['spam']*n)
>
>      # (2) can call functions from inside the namespace
>      breakfast = spam(5)
>
>      # (3) no "cls" or "self" argument
>      def lunch():
>          # (4) can access variables using their undotted name
>          return breakfast + ' and eggs'
>
>      def supper():
>          # (5) likewise functions (a special case of #4)
>          return lunch() + ' and a fried slice of spam'
>
>      def mutate(n):
>          # global inside the namespace refers to the namespace,
>          # not the surrounding module
>          global breakfast
>          breakfast = spam(5)

> Can you do all of that with an ordinary class?

You can get #2 already, but not the rest (without your spiffy code ;) :

Python 3.5.1+ (3.5:f840608f79da, Apr 14 2016, 12:29:06)
[GCC 4.8.2] on linux
Type "help", "copyright", "credits" or "license" for more information.
 >>> class Huh:
...   def blah(text):
...     print('blah blah %s blah blah blah' % text)
...   blah('whatever')
...
blah blah whatever blah blah blah

--
~Ethan~

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Thread

Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-02 00:13 +1000
  Re: Namespaces are one honking great idea Random832 <random832@fastmail.com> - 2016-07-01 10:40 -0400
  Re: Namespaces are one honking great idea BartC <bc@freeuk.com> - 2016-07-01 15:49 +0100
    Re: Namespaces are one honking great idea Chris Angelico <rosuav@gmail.com> - 2016-07-02 03:13 +1000
    Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-02 03:46 +1000
    Re: Namespaces are one honking great idea Rustom Mody <rustompmody@gmail.com> - 2016-07-01 19:26 -0700
  Re: Namespaces are one honking great idea Ethan Furman <ethan@stoneleaf.us> - 2016-07-01 09:00 -0700
    Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-02 03:10 +1000
      Re: Namespaces are one honking great idea Ethan Furman <ethan@stoneleaf.us> - 2016-07-01 12:29 -0700
        Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-02 11:07 +1000
          Re: Namespaces are one honking great idea Kevin Conway <kevinjacobconway@gmail.com> - 2016-07-02 01:50 +0000
            Re: Namespaces are one honking great idea Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-01 19:55 -0700
            Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-03 13:22 +1000
          Re: Namespaces are one honking great idea Random832 <random832@fastmail.com> - 2016-07-02 00:59 -0400
          Re: Namespaces are one honking great idea Kevin Conway <kevinjacobconway@gmail.com> - 2016-07-02 15:34 +0000
            Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-03 13:44 +1000
              Re: Namespaces are one honking great idea Ethan Furman <ethan@stoneleaf.us> - 2016-07-02 22:14 -0700
              Re: Namespaces are one honking great idea Kevin Conway <kevinjacobconway@gmail.com> - 2016-07-03 22:02 +0000
                Re: Namespaces are one honking great idea Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-03 16:21 -0700
                Re: Namespaces are one honking great idea BartC <bc@freeuk.com> - 2016-07-04 01:19 +0100
              Re: Namespaces are one honking great idea Ethan Furman <ethan@stoneleaf.us> - 2016-07-03 21:01 -0700
          Re: Namespaces are one honking great idea Ethan Furman <ethan@stoneleaf.us> - 2016-07-02 16:28 -0700
  Re: Namespaces are one honking great idea Chris Angelico <rosuav@gmail.com> - 2016-07-04 21:37 +1000
    Re: Namespaces are one honking great idea Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-04 15:09 -0700
      Re: Namespaces are one honking great idea Lawrence D’Oliveiro <lawrencedo99@gmail.com> - 2016-07-04 15:11 -0700
  Re: Namespaces are one honking great idea jmp <jeanmichel@sequans.com> - 2016-07-04 17:58 +0200
  Re: Namespaces are one honking great idea Chris Angelico <rosuav@gmail.com> - 2016-07-05 12:58 +1000
    Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-05 13:35 +1000
      Re: Namespaces are one honking great idea Chris Angelico <rosuav@gmail.com> - 2016-07-05 13:47 +1000
        Re: Namespaces are one honking great idea Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2016-07-05 16:09 +1000
          A nestedmodule decorator (Re: Namespaces are one honking great idea) Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2016-07-05 21:10 +1200
            Improved nestedmodule decorator implementation Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2016-07-05 21:31 +1200
              Re: Improved nestedmodule decorator implementation Steven D'Aprano <steve@pearwood.info> - 2016-07-05 20:54 +1000
  Re: Namespaces are one honking great idea Steven D'Aprano <steve@pearwood.info> - 2016-07-05 12:34 +1000
  Re: Namespaces are one honking great idea jmp <jeanmichel@sequans.com> - 2016-07-04 13:23 +0200
  Re: Namespaces are one honking great idea carlosjosepita@gmail.com - 2016-07-09 07:05 -0700

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