Hi,
I suspect it's not something anyone's likely to come across often, but
if you try to rebind a method on a built-in class, no exception will be
thrown but it will not be changed. An example:
You can rebind methods on regular classes easily:
---
>>> class C:
... def m(self):
... return 2
...
>>> c = C()
>>> c.m()
2
>>> def n():
... return 3
...
>>> c.m = n
>>> c.m()
3
---
However, when you try to do this with a CLR class there's no warning,
but it doesn't work:
---
>>> f = Form()
>>> f.ToString()
'System.Windows.Forms.Form, Text: '
>>> def newToString():
... return "Hello, world!"
...
>>> f.ToString = newToString
>>> f.ToString()
'System.Windows.Forms.Form, Text: '
>>> f.ToString == newToString
False
---
The behaviour when you try to set arbitrary attributes on the built-in
classes is nicer, I think:
---
>>> f.foobar = 23
Traceback (most recent call last):
at <shell>
TypeError: can't set arbitrary attributes on built-in type
System.Windows.Forms.Form
---
I've confirmed this in the beta and in 0.9.5
(I hasten to add that I'm not recommending rebinding methods as standard
practive...)
Cheers,
Giles
--
Giles Thomas
Resolver Systems
[EMAIL PROTECTED]
We're hiring! http://www.resolversystems.com/jobs/
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