I was under the impression that you could tack methods onto an object at any time, your example almost works with old style classes and would with a function instead of a method.
>>> class A:
... def __init__(self):
... self.__call__ = A.hello
... def hello(self):
... print "Hello, world!"
...
>>> a = A()
>>> a()
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: unbound method hello() must be called with A instance as first argument (got nothing instead)
>>> a(a)
Hello, world!
>>>
So now all I need to know is why now with new style classes the special functions need to be defined on the class instead of attached to the instance at any time.
On 08/02/06, Delaney, Timothy (Tim) <[EMAIL PROTECTED]> wrote:
adam johnson wrote:
> Hi All.
> I was wondering why defining a __call__ attribute for a module
> doesn't make it actually callable.
For the same reason that the following doesn't work
class A (object):
def __init__(self):
self.__call__ = A.hello
def hello (self):
print 'Hello, world!'
a = A()
a()
Traceback (most recent call last):
File "D:\Python\modules\testclasscall.py", line 10, in ?
a()
TypeError: 'A' object is not callable
The __call__ attribute must be defined on the class (or type) - not on
the instance. A module is an instance of <type 'module'>.
Tim Delaney
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