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Groups > comp.lang.python > #53434

Re: Encapsulation unpythonic?

Date 2013-09-01 13:33 -0700
From Ethan Furman <ethan@stoneleaf.us>
Subject Re: Encapsulation unpythonic?
References (6 earlier) <5222f675$0$6599$c3e8da3$5496439d@news.astraweb.com> <mailman.441.1378023704.19984.python-list@python.org> <9c11126f-93e8-461c-b487-bafc6b146269@googlegroups.com> <mailman.455.1378062400.19984.python-list@python.org> <roy-F4F03B.15130601092013@news.panix.com>
Newsgroups comp.lang.python
Message-ID <mailman.460.1378071286.19984.python-list@python.org> (permalink)

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On 09/01/2013 12:13 PM, Roy Smith wrote:
> In article <mailman.455.1378062400.19984.python-list@python.org>,
>   Ethan Furman <ethan@stoneleaf.us> wrote:
>
>> On 09/01/2013 03:09 AM, Fabrice Pombet wrote:
>>>
>>> So I guess that we are actually all agreeing on this one.
>>
>> No, we are not.
>>
>> "encapsulation" != "inaccessible except by getters/setters"
>
> Nothing is accessible in Python except via getters and setters.  The
> only difference between Python and, say, C++ in this regard is that the
> Python compiler writes them for you most of the time and doesn't make
> you put ()'s at the end of the name :-)

class Javaesque:

     __value = None

     def get_value(self):
         return self.__value

     def set_value(self, new_value):
         validate(new_value)
         self.__value = new_value


class ProtectedPython:

     _value = None

     @property
     def value(self):
         return self._value

     @value.setter
     def value(self, new_value)
         validate(new_value)
         self._value = new_value

class PlainPython:

     value = None


In the Javaesque class we see the unPythonic way of using getters/setters; in the ProtectedPython* class we see the 
pythonic way of providing getters/setters**; in the PlainPython class we have the standard, unprotected, direct access 
to the class attribute.

No where in PlainPython is a getter/setter defined, nor does Python define one for us behind our backs.

If you have evidence to the contrary I'd like to see it.


* Not the best name, but oh well.
** In Python, using @property makes getter/setter usage look just like normal attribute usage, which is cool.

--
~Ethan~

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Thread

Encapsulation unpythonic? fsaldan1@gmail.com - 2013-08-17 05:26 -0700
  Re: Encapsulation unpythonic? Skip Montanaro <skip@pobox.com> - 2013-08-17 07:54 -0500
  Re: Encapsulation unpythonic? David <bouncingcats@gmail.com> - 2013-08-17 23:05 +1000
  Re: Encapsulation unpythonic? Chris Angelico <rosuav@gmail.com> - 2013-08-17 16:50 +0100
  Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-08-17 16:17 +0000
    Re: Encapsulation unpythonic? Joshua Landau <joshua@landau.ws> - 2013-08-18 18:15 +0100
      Re: Encapsulation unpythonic? Steven D'Aprano <steve@pearwood.info> - 2013-08-19 07:05 +0000
        Re: Encapsulation unpythonic? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-08-19 18:57 -0400
        Re: Encapsulation unpythonic? random832@fastmail.us - 2013-08-21 12:52 -0400
          Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-08-22 02:06 +0000
        Re: Encapsulation unpythonic? Ian Kelly <ian.g.kelly@gmail.com> - 2013-08-21 16:02 -0600
  Re: Encapsulation unpythonic? Gary Herron <gary.herron@islandtraining.com> - 2013-08-17 13:16 -0700
  Re: Encapsulation unpythonic? Terry Reedy <tjreedy@udel.edu> - 2013-08-17 17:22 -0400
  Re: Encapsulation unpythonic? Chris Angelico <rosuav@gmail.com> - 2013-08-18 01:59 +0100
  Re: Encapsulation unpythonic? chaz2cry@gmail.com - 2013-08-22 19:12 -0700
  Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-30 10:43 -0700
    Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-08-31 02:35 +0000
      Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-30 23:07 -0700
        Re: Encapsulation unpythonic? Marco Buttu <marco.buttu@gmail.com> - 2013-08-31 08:49 +0200
        Re: Encapsulation unpythonic? Gary Herron <gherron@digipen.edu> - 2013-08-31 00:03 -0700
          Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-31 00:42 -0700
            Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-31 01:00 -0700
        Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-08-31 11:46 +0000
          Re: Encapsulation unpythonic? Ned Batchelder <ned@nedbatchelder.com> - 2013-08-31 08:41 -0400
            Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-31 05:49 -0700
          Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-08-31 05:57 -0700
            Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-01 08:10 +0000
              Re: Encapsulation unpythonic? Chris Angelico <rosuav@gmail.com> - 2013-09-01 18:21 +1000
                Re: Encapsulation unpythonic? Fabrice Pombet <fp2161@gmail.com> - 2013-09-01 03:09 -0700
                Re: Encapsulation unpythonic? Ethan Furman <ethan@stoneleaf.us> - 2013-09-01 11:42 -0700
                Re: Encapsulation unpythonic? Roy Smith <roy@panix.com> - 2013-09-01 15:13 -0400
                Re: Encapsulation unpythonic? Ethan Furman <ethan@stoneleaf.us> - 2013-09-01 13:33 -0700
                Re: Encapsulation unpythonic? Tim Delaney <timothy.c.delaney@gmail.com> - 2013-09-02 07:54 +1000
                Re: Encapsulation unpythonic? Roy Smith <roy@panix.com> - 2013-09-01 18:02 -0400
                Re: Encapsulation unpythonic? Ethan Furman <ethan@stoneleaf.us> - 2013-09-01 17:24 -0700
                Re: Encapsulation unpythonic? Roy Smith <roy@panix.com> - 2013-09-01 20:59 -0400
                Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-02 02:57 +0000
                Re: Encapsulation unpythonic? Ethan Furman <ethan@stoneleaf.us> - 2013-09-01 21:15 -0700
                Re: Encapsulation unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-02 01:57 +0000
              Re: Encapsulation unpythonic? Ben Finney <ben+python@benfinney.id.au> - 2013-09-02 09:32 +1000
                Re: Encapsulation unpythonic? Roy Smith <roy@panix.com> - 2013-09-01 20:52 -0400
          Re: Encapsulation unpythonic? "Rhodri James" <rhodri@wildebst.demon.co.uk> - 2013-09-03 00:29 +0100
            Re: Encapsulation unpythonic? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-09-03 22:41 -0400
        Re: Encapsulation unpythonic? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-08-31 13:31 -0400
        Re: Encapsulation unpythonic? Tim Delaney <timothy.c.delaney@gmail.com> - 2013-09-01 03:47 +1000
    Re: Encapsulation unpythonic? 88888 Dihedral <dihedral88888@gmail.com> - 2013-09-02 14:43 -0700

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