Re: Dynamically adding methods to a class...

[Gabriel Genellina]

En Tue, 29 Jul 2008 01:17:13 -0300, Piyush Anonymous
<piyush.subscri ption@gmail.com escribi�:

class MyObject:
def __init__(self, name):
self.name = name
>
def do_this_default (self):
print "default do_this implementation for %s" % self.name
>
def custom_do_this( ): #method to be added
print "custom do_this implementation for %s" % self.name

You forget the self argument (this explains the error you got).

def funcToMethod(fu nc,clas,method_ name=None):
"""Adds func to class so it is an accessible method; use method_name
to
specify the name to be used for calling the method.
The new method is accessible to any instance immediately."""
import new
method = new.instancemet hod(func,None,c las)
print method
if not method_name: method_name=fun c.__name__
clas.__dict__[method_name]=func

It's a lot easier than that; just add the *function* object to the class
namespace:
setattr(clas, method_name, func)
If you know the name when you write the code, just set the attribute:

pyo = MyObject("hello ")
pyMyObject.cust om_do_this = custom_do_this
pyo.custom_do_t his()
custom do_this implementation for hello

new.instancemet hod is useful to add specific methods to individual
instances, but it's not used to add methods globally to the class.

Error I am getting;
TypeError: custom_do_this( ) takes no arguments (1 given)

Add the self argument and you're done.

Why am I getting it?
>
Also how can I do this in new style class (inherited from 'object')?

It's the same thing, no difference.

--
Gabriel Genellina