"Ron Adam" <[EMAIL PROTECTED]> wrote:
> I'm trying to implement simple svg style colored complex objects in
> tkinter and want to be able to inherit default values from other
> previously defined objects.
>
> I want to something roughly similar to ...
>
> class shape(object):
> def __init__(self, **kwds):
> # set a bunch of general defaults here.
> self.__dict__.update(kwds)
> def draw(self, x=0, y=0, scale=1.0):
> # draw the object
>
> hello = shape(text='hello')
> redhello = hello(color='red')
> largeredhello = redhello(size=100)
> largeredhiya = largeredhello(text='Hiya!')
> largeredhiya.draw(c, 20, 50)
>
>
> I think this will need to require __new__ or some other way to do it.
> But I'm not use how to get this kind of behavior. Maybe the simplest
> way is to call a method.
>
> redhello = hello.makenew( color='red' )
Just name it '__call__' instead of makenew and you have the syntax sugar you
want:
def __call__(self, **kwds):
new = self.__class__(**self.__dict__)
new.__dict__.update(kwds)
return new
Personally I would prefer an explicit method name, e.g. 'copy'; hiding the fact
that 'shape' is a
class while the rest are instances is likely to cause more trouble than it's
worth.
George
--
http://mail.python.org/mailman/listinfo/python-list
