On Dec 22, 11:03 pm, Steven D'Aprano <[EMAIL PROTECTED]
cybersource.com.au> wrote:
> When you call a new-style class, the __new__ method is called with the
> user-supplied arguments, followed by the __init__ method with the same
> arguments.
>
Only if __new__ returns an object of the type passed into __new__.
Otherwise, __init__ is not called.
> I would like to modify the arguments after the __new__ method is called
> but before the __init__ method, somewhat like this:
>
What's your use-case? I mean, why not just do this in __init__
instead of __new__?
> >>> class Spam(object):
>
> ... def __new__(cls, *args):
> ... print "__new__", args
> ... x = object.__new__(cls)
> ... args = ['spam spam spam']
> ... return x
> ... def __init__(self, *args):
> ... print "__init__", args # hope to get 'spam spam spam'
> ... return None
>
> but naturally it doesn't work:
>
> >>> s = Spam('spam and eggs', 'tomato', 'beans are off')
>
> __new__ ('spam and eggs', 'tomato', 'beans are off')
> __init__ ('spam and eggs', 'tomato', 'beans are off')
>
> Is there any way to do this, or am I all outta luck?
>
>From what I can tell from http://docs.python.org/ref/customization.html,
you are out of luck doing it this way unless you jury rig some way to
have __new__ return an object of a different type.
--Nathan Davis
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