Re: [SQLObject] New style classes and __init__ vs _init

[Bud P. B. <bu...@si...>]

Hi Edmund,

I think what I know about this issue, I read from either
in Andrew Kuchlin's What's new in 2.2
http://www.python.org/doc/2.2.1/whatsnew/
or in Guido's essay
http://www.python.org/doc/2.2.1/whatsnew/

I agree with Ian that every time you call the class, both __new__ and
__init__ of the class are executed.  

More precisely, if

class C(object):
  def __init__(self):
    pass

c = C() will translate to something along the following lines:
c = C.__new__(C) followed by C.__init__(c) 

But as I pointed out before, calling the class is not the only way of
ending up with a valid instance of C.  It is possible, and often
useful to just call __new__ and to initialize the state of the object
(in most cases the value of __dict__) in a different way.  This is
what is done for example by pickle.  

--b



On Mon, 02 Jun 2003 20:25:35 -0400
Edmund Lian <el...@in...> wrote:

> In the SQLObject docs, Ian writes:
> 
> "With new-style classes, __init__ is called everytime the class is 
> called. That means it's called when an object is just fetched from the 
> cache"
> 
> This was a bit surprising to me, so I Googled to find discussion of 
> this, but came up empty. Can anybody point me to a discussion of this?
> 
> ...Edmund.
> 
> 
> 
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