Le 26/09/2019 à 14:20, ast a écrit :
Hello
In the following code found here:
https://www.pythonsheets.com/notes/python-object.html
__init__ is not invoked when we create an object
with "o = ClassB("Hello")". I don't understand why.
I know the correct way to define __new__ is to write
"return object.__new__(cls, arg)" and not "return object"
>>> class ClassB(object):
... def __new__(cls, arg):
... print('__new__ ' + arg)
... return object
... def __init__(self, arg):
... print('__init__ ' + arg)
...
>>> o = ClassB("Hello")
__new__ Hello
Normaly, when running "o = ClassB("Hello")", we first run
__call__ from type of ClassB which is type. This __call__
method is supposed to launch __new__ from ClassB and then
__init__ from classB too. The output of __new__ is mapped
to self parameter of __init__.
But it seems things don't work like that here. Why ?
Maybe __init__ is called by object.__new__ call and not
by type.__call_ as I thought.
So of course here without any call to object.__new__, __init__
is not called
--
https://mail.python.org/mailman/listinfo/python-list
