Path: csiph.com!usenet.pasdenom.info!gegeweb.org!usenet-fr.net!nerim.net!novso.com!newsfeed.xs4all.nl!newsfeed4.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail
MIME-Version: 1.0
In-Reply-To: <5B80DD153D7D744689F57F4FB69AF47418683AD8@SCACMX008.exchad.jpmchase.net>
References: <14d50efb-e88b-4259-960a-97ef58e345d8@googlegroups.com> <5B80DD153D7D744689F57F4FB69AF47418683AD8@SCACMX008.exchad.jpmchase.net>
From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Thu, 22 Aug 2013 15:59:17 -0600
Subject: Re: Can a child access parent attributes if that child added post-hoc as an attribute to the parent?
To: Python <python-list@python.org>
Content-Type: text/plain; charset=ISO-8859-1
Precedence: list
Newsgroups: comp.lang.python
Message-ID: <mailman.143.1377208801.19984.python-list@python.org>
Lines: 43
NNTP-Posting-Host: 2001:888:2000:d::a6
Xref: csiph.com comp.lang.python:52847

On Thu, Aug 22, 2013 at 3:26 PM, Prasad, Ramit
<ramit.prasad@jpmorgan.com.dmarc.invalid> wrote:
> Bitswapper wrote:
>>
>> So I have a parent and child class:
>>
>>
>> class Map(object):
>>     def __init__(self, name=''):
>>         self.mapName = name
>>         self.rules = {}
>>
>> class Rule(Map):
>>     def __init__(self, number):
>>         Map.__init__(self)
>>         self.number = number
>
> This means that rules will never have a name. I think you need
>       def __init__(self, name='', number=None):
>           Map.__init__(self, name)
>           self.number = number

No, that's still wrong.  The OP talks abut maps having names, not
rules having names.  Unless a Rule is-a Map, which sounds unlikely,
Rule should not be inheriting from Map in the first place.

>> It seems to me what I'm trying to do is link an arbitrary child instance to an arbitrary instance of a
>> parent class, which in this case would be handy  Because I'd like to populate a map with rules and
>> print the rules including the parent map name for each rule.  I'm just not sure how I would go about
>> doing this in python.

You'll need to keep a reference to the Map on each Rule instance.  So
instead of self.mapName you'll have self.map.mapName.  Your Rule class
should probably look something like this:

class Rule(object):
    def __init__(self, map, number):
        self.map = map
        self.number = number

And then when you construct it you'll need to tell it what map it belongs to:

    rule = Rule(map, 1)