How can I define class methods outside of the class?

[bruno.desthuilliers at gmail.com]

On 2 déc, 15:45, Jeremy <jlcon... at gmail.com> wrote:
> On Dec 1, 10:47 pm, James Mills <prolo... at shortcircuit.net.au> wrote:
>
>
>
> > On Thu, Dec 2, 2010 at 3:36 PM, Jeremy <jlcon... at gmail.com> wrote:
> > > I have some methods that I need (would like) to define outside of the
> > > class.  I know this can be done by defining the function and then
> > > setting it equal to some member of an instance of the class.  But,
> > > because of the complexity of what I'm doing (I have to set many
> > > functions as class methods) I would rather not do this.  Can someone
> > > show me how to do this?  Is it even possible?  Can decorators be used
> > > here?
>
> > Do you mean something like this ?
>
> > @classmethod
> > def foo(cls):
> >     print "I am the foo classmethod on %r" % cls
>
> > class Foo(object):
> >     pass
>
> > Foo.foo = foo
>
> > cheers
> > James
>
> Thanks, James.  That is almost exactly what I want.  However, I want to avoid doing
>
> Foo.foo = foo
>
> Is this going to be possible?  

def patch(cls):
   def _patch(func):
       setattr(cls, func.__name__, func)
       return func
   return _patch

class Foo(object): pass


@patch(Foo)
def bar(self):
    print self

f = Foo()
f.bar()


> I'm trying to understand how decorators
> are used.  Are they really necessary in this example?

In the above example, the classmethod type was used as a decorator to
turn the function into, well, a classmethod (read my other answer in
this thread if you don't know what a classmethod is).