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:
In python, writting obj.method() will be translated into method(obj) so
any instance method has a #arg + 1 arguments, something you'll get
familiar with.
Furthermore, Complex(3.0, -4.5) invokes 2 functions : __new__ and
__init__. __new__ is the "constructor", this is the function that
returns an instance. __init__ is an initializer, at the time it's called
the instance already exists and is viable.
*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)
Python uses a different data model, it is a very good idea to mark
theses differences using an explicit distinct syntax so that people
won't jump into false conclusions like "it's like C or Java". It is not.
JM
JM
--
http://mail.python.org/mailman/listinfo/python-list
