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Re: Infinitely nested containers

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Date Fri, 21 Nov 2014 18:03:49 +1100
Subject Re: Infinitely nested containers
From Chris Angelico <rosuav@gmail.com>
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On Fri, Nov 21, 2014 at 4:54 PM, Gill Shen <gillarete@gmail.com> wrote:
> How is this behavior implemented under the hood? And why is this allowed at all? Is it just a curiosity or can you do something useful with it?

Simple: The list contains itself. When you dereference the list, you
get back the original list. It does have value; you just have to be
careful of any recursive operation like printing it out - the repr()
for a list carefully checks for this.

ChrisA

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Thread

Infinitely nested containers Gill Shen <gillarete@gmail.com> - 2014-11-20 21:54 -0800
  Re: Infinitely nested containers Marko Rauhamaa <marko@pacujo.net> - 2014-11-21 09:00 +0200
    Re: Infinitely nested containers random832@fastmail.us - 2014-11-21 12:39 -0500
      Re: Infinitely nested containers Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-11-22 15:43 +1100
        Re: Infinitely nested containers Chris Angelico <rosuav@gmail.com> - 2014-11-22 15:50 +1100
          Re: Infinitely nested containers Rustom Mody <rustompmody@gmail.com> - 2014-11-21 21:02 -0800
            Re: Infinitely nested containers Chris Angelico <rosuav@gmail.com> - 2014-11-22 16:09 +1100
              Re: Infinitely nested containers Rustom Mody <rustompmody@gmail.com> - 2014-11-21 22:03 -0800
        Re: Infinitely nested containers Ethan Furman <ethan@stoneleaf.us> - 2014-11-22 11:50 -0800
          Re: Infinitely nested containers Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-11-23 16:59 +1100
            Re: Infinitely nested containers random832@fastmail.us - 2014-11-23 01:39 -0500
    Re: Infinitely nested containers Chris Angelico <rosuav@gmail.com> - 2014-11-22 04:47 +1100
    Re: Infinitely nested containers random832@fastmail.us - 2014-11-21 12:50 -0500
    Re: Infinitely nested containers Ian Kelly <ian.g.kelly@gmail.com> - 2014-11-21 11:37 -0700
    Re: Infinitely nested containers Zachary Ware <zachary.ware+pylist@gmail.com> - 2014-11-21 13:30 -0600
    Re: Infinitely nested containers Terry Reedy <tjreedy@udel.edu> - 2014-11-22 16:57 -0500
  Re: Infinitely nested containers Chris Angelico <rosuav@gmail.com> - 2014-11-21 18:03 +1100
  Re: Infinitely nested containers Ian Kelly <ian.g.kelly@gmail.com> - 2014-11-21 10:13 -0700

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