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Re: class implementation

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On 30/9/2013 08:41, markotaht@gmail.com wrote:

> under variables, i mean, the int's and lists and strings and floats that the parent class uses. IF in parent class there is variable called location, then can i use the same variable in my sub class.

Python doesn't actually have variables, but the things it documents as
variables are local names within a method.  Those are not visible
outside of the method, regardless of whether you're in a class or a
subclass.

But perhaps you mean attributes.  There are both class attributes and
instance attributes, and the behavior is quite different.  Roughly
speaking a class attribute occurs only once per class, and all code can
read its value with either Class.my_attrib   or  instance.my_attrib.  It
can be written with Class.my_attrib.

On the other hand, instance attributes are usable by 
instance.my_attrib, regardless of whether the instance is a base class
or a child class.  Each instance of the class gets a separate copy of
such an attribute.  They are normally defined in the __init__() method.

If you don't happen to know the difference between a class an an
instance of that class, then all the above will look like gibberish, and
you need to do some studying first.

-- 
DaveA

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class implementation markotaht@gmail.com - 2013-09-30 01:43 -0700
  Re: class implementation Peter Otten <__peter__@web.de> - 2013-09-30 11:03 +0200
  Re: class implementation markotaht@gmail.com - 2013-09-30 02:10 -0700
    Re: class implementation Peter Otten <__peter__@web.de> - 2013-09-30 11:27 +0200
  Re: class implementation markotaht@gmail.com - 2013-09-30 05:41 -0700
    Re: class implementation Peter Otten <__peter__@web.de> - 2013-09-30 15:02 +0200
    Re: class implementation Joel Goldstick <joel.goldstick@gmail.com> - 2013-09-30 09:21 -0400
    Re: class implementation Piet van Oostrum <piet@vanoostrum.org> - 2013-09-30 13:32 -0400
    Re: class implementation Dave Angel <davea@davea.name> - 2013-09-30 19:34 +0000
      Re: class implementation 88888 Dihedral <dihedral88888@gmail.com> - 2013-10-01 00:01 -0700
    Re: class implementation Ned Batchelder <ned@nedbatchelder.com> - 2013-09-30 17:28 -0400
      Re: class implementation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-30 23:45 +0000
        Re: class implementation Ethan Furman <ethan@stoneleaf.us> - 2013-09-30 17:31 -0700
    Re: class implementation random832@fastmail.us - 2013-09-30 17:49 -0400
    Python variables?  [was Re: class implementation] Ethan Furman <ethan@stoneleaf.us> - 2013-09-30 15:02 -0700
    Re: Python variables? Ben Finney <ben+python@benfinney.id.au> - 2013-10-01 08:37 +1000
    Re: Python variables?  [was Re: class implementation] Ned Batchelder <ned@nedbatchelder.com> - 2013-09-30 19:45 -0400
      Re: Python variables?  [was Re: class implementation] "Rhodri James" <rhodri@wildebst.demon.co.uk> - 2013-10-01 01:29 +0100
    Re: Python variables? Ned Batchelder <ned@nedbatchelder.com> - 2013-09-30 19:47 -0400
      Re: Python variables? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-01 01:03 +0000
        Re: Python variables? Ned Batchelder <ned@nedbatchelder.com> - 2013-09-30 21:28 -0400
    Re: class implementation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-01 00:19 +0000
  Re: class implementation markotaht@gmail.com - 2013-10-06 06:15 -0700
    Re: class implementation Terry Reedy <tjreedy@udel.edu> - 2013-10-06 15:52 -0400
    Re: class implementation Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-10-07 01:24 +0000
  Re: class implementation markotaht@gmail.com - 2013-10-08 01:20 -0700
    Re: class implementation Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-10-08 09:41 +0100
    Re: class implementation Dave Angel <davea@davea.name> - 2013-10-08 10:31 +0000
    Re: class implementation Cameron Simpson <cs@zip.com.au> - 2013-10-09 10:55 +1100
      Re: class implementation markotaht@gmail.com - 2013-10-10 11:34 -0700
        Re: class implementation Cameron Simpson <cs@zip.com.au> - 2013-10-11 09:07 +1100
        Re: class implementation Piet van Oostrum <piet@vanoostrum.org> - 2013-10-10 19:29 -0400
          Re: class implementation Ben Finney <ben+python@benfinney.id.au> - 2013-10-11 10:51 +1100
  Re: class implementation markotaht@gmail.com - 2013-10-08 07:05 -0700
    Re: class implementation "Rhodri James" <rhodri@wildebst.demon.co.uk> - 2013-10-09 00:41 +0100

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