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Self modifying systems question

Duncan Booth duncan at NOSPAMrcp.co.uk
Wed Apr 30 08:37:04 EDT 2003 
tebeka at cs.bgu.ac.il (Miki Tebeka) wrote in 
news:33803989.0304300426.402cd1ef at posting.google.com:

>> Self modifying code is a well known technology. Has anyone done this in
>> Python? What I'm seeking for is examples of software that adds to
>> itself (methods and variables) in runtime. I'd like an instantiated 
>> object to
>> be able to add a method to itself.
>>>> class A:
>      pass
> 
>>>> a = A()
>>>> a.f = lambda x: x + 1
>>>> a.f(100)
> 101

That doesn't really add a method to 'a', it adds a function, but the 
function doesn't have any way to determine which instance it was called on. 
You need to simulate the same binding that you get when calling a method 
defined in the class.

Here is one way to add a method to an instance (Python 2.2 and on):

>>> def f(self):
	return self.x + 1

>>> class A: pass

>>> a.x = 5
>>> a.f = f.__get__(a)
>>> a.f()
6
>>>

-- 
Duncan Booth                                             duncan at rcp.co.uk
int month(char *p){return(124864/((p[0]+p[1]-p[2]&0x1f)+1)%12)["\5\x8\3"
"\6\7\xb\1\x9\xa\2\0\4"];} // Who said my code was obscure?
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