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From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Why do class methods always need 'self' as the first parameter?
Date: Wed, 31 Aug 2011 12:30:59 -0400
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On 8/31/2011 10:35 AM, T. Goodchild wrote:

> But one of the things that bugs me is the requirement that all class
> methods have 'self' as their first parameter.  On a gut level, to me
> this seems to be at odds with Python=E2=80=99s dedication to simplicity=
=2E

Actually, it is a consequence of Python's dedication to simplicity. A=20
method is simply a function that is an attribute of a class. (This is=20
even clearer in Py 3.) Hence, there is no special syntax for methods.

Consider

def double(obj): return 2*obj.value

class C:
     def __init__(self, val):
         self.value =3D val

c =3D C(3)
C.double =3D double
c.doub =3D double
# not c.double as that would mask access to C.double in c.double() below
print(double(c), C.double(c), c.double(), c.doub(c))
# 6 6 6 6

--=20
Terry Jan Reedy