Overriding the __new__ method

[Christoph Groth]

Hello,

The essay "Unifying types and classes in Python 2.2"
http://www.python.org/2.2.1/descrintro.html says in section
"Overriding the __new__ method":

<quote>
This class isn't very useful (it's not even the right way to go about
unit conversions) but it shows how to extend the constructor of an
immutable type. If instead of __new__ we had tried to override
__init__, it wouldn't have worked:

    >>> class inch(float):
    ...     "THIS DOESN'T WORK!!!"
    ...     def __init__(self, arg=0.0):
    ...         float.__init__(self, arg*0.0254)
    ...
    >>> print inch(12)
    12.0
    >>> 
</quote>

Well, I tried this with Python 2.2.1 and it _does_ work:

piglet:~$ python
Python 2.2.1 (#1, Sep  7 2002, 14:34:30) 
[GCC 2.95.4 20011002 (Debian prerelease)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> class inch(float):
...     def __init__(self, arg=0.0):
...         float.__init__(self, arg*0.0254)
... 
>>> print inch(12)
12.0

Now I'm a bit puzzled.

Thank you,

Christoph
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