Proper syntax for adding methods to a class instance dynamically?

[Geoff Gerrietts]

Quoting Fernando Pérez (fperez528 at yahoo.com):
> I'd like to know what the proper way to do this is. I've been using the new 
> module with new.instancemethod(), but the docstring for new isn't very 
> confidence inducing:
> 
> Is there a simpler, perhaps 'safer' way to achieve the same result? What I 
> want is to have code which runs after an instance of a certain class has been 
> created and which can add new methods to the class instance. I'd also like to 
> know how to add them to the whole class. I have some solutions in store but I 
> feel they're kind of kludgy.

I don't know much (read: anything) about instance methods, or how to
generate them, etc. So I can't help you much there. But, for adding a
method to a class, that's easy:

>>> class Spam:
...   pass
...  
>>> def eggs(self, stuff):
...   print self, stuff
... 
>>> Spam.eggs = eggs
>>> i = Spam()
>>> i.eggs("stuff")
<__main__.Spam instance at 0x81500e4> stuff


That'll work for a new-style class, too.

--G.

-- 
Geoff Gerrietts <geoff at gerrietts net>          http://www.gerrietts.net/
     "Now, now my good man, this is no time for making enemies." 
      --Voltaire, on his deathbed, when asked to renounce Satan