On 6/28/10 1:13 PM, Emile van Sebille wrote:
On 6/28/2010 12:02 PM Benjamin Kaplan said...
Just to save the OP some trouble later on: this optimization is done
for most of the __*__ methods. Overriding __add__ on an instance won't
change the behavior of a + b.
ActivePython 2.4.1 Build 247 (ActiveState Corp.) based on
Python 2.4.1 (#65, Jun 20 2005, 17:01:55) [MSC v.1310 32 bit (Intel)] on
win32
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>>> class Test: pass
...
>>> i = Test()
>>> i+1
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: unsupported operand type(s) for +: 'instance' and 'int'
>>> def __add__(self): return 6
...
>>> i.__add__ = __add__
>>> i+1
6
>>>
Was this in reference to a specific python version?
No, its a reference to new-style vs old-style classes. If Test inherits
from object, it won't work. Its one of several subtle behaviorial
differences between old/new classes.
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