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Subject: Re: Python classes: Simplify?
From: "J. Cliff Dyer" <jcd@sdf.lonestar.org>
To: Andrea Crotti <andrea.crotti.0@gmail.com>
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Date: Thu, 22 Mar 2012 14:12:32 -0400
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Cc: python-list@python.org, Steven Lehar <slehar@gmail.com>
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Xref: csiph.com comp.lang.python:22036

The issue of explicitly naming a "self" parameter has been discussed in
depth on a number of occasions.  I recommend a google search for "python
implicit self" for some of the reasons why it exists.  Here's what Guido
has to say about it:

http://neopythonic.blogspot.com/2008/10/why-explicit-self-has-to-stay.html

Cheers,
Cliff



On Thu, 2012-03-22 at 13:15 +0000, Andrea Crotti wrote:
> On 03/22/2012 10:51 AM, Steven Lehar wrote: 
> > It seems to me that the Python class system is needlessly confusing.
> > Am I missing something? 
> > 
> > 
> > For example in the class Complex given in the documentation
> > 
> > 
> > class Complex:
> >     def __init__(self, realpart, imagpart):
> >         self.r = realpart
> >         self.i = imagpart
> > 
> > 
> > x = Complex(3.0, -4.5)
> > 
> > 
> > I initially found it profoundly confusing that __init__( ) calls for
> > 3 arguments, but you call Complex( ) with 2. Furthermore, why not
> > call the initialization function after the class name as is done in
> > other languages? Isn't that the simplest conceptually? Demonstrating
> > with the above example:
> > 
> > 
> > class Complex:
> >     def Complex(realpart, imagpart):
> >         Complex.r = realpart
> >         Complex.i = imagpart
> > 
> > 
> > x = Complex(3.0, -4.5)
> > 
> > 
> > Is there a good reason why classes cannot be defined that way?
> > (Besides the problem of backward-compatibility)
> > 
> > 
> 
> Some time ago I saw some nasty hack that allowed you to drop the self
> in the method declaration,
> using some crazy metaclass trick, but that's really not a good idea ;)
> 
> I agree that is counter-intuitive but just set your editor to do that
> for you and you will be fine..
> 
> in my emacs
> - s TAB -> self
> - . TAB -> self.
> - m TAB -> def ${1:method}(self$2):
>                          $0
> 
> so I never actually write the self..