Setting class variable during instantiation when using a factory in python

Question

I have a class factory, very similar to the one here. I want to set a variable that the created class will have access to, when calling createShape. How do you do this pythonicly?

For example:

foo = 'bar'
circle = ShapeFactory.createShape('circle', foo)
print circle.foo >>> bar

however, since createShape is static, I can't add

self.foo = foo

to the createShape method.

Obviously all shapes would implement this parameter.

Answer 1

You can't do it with self, but you can still do it with the object created in createShape. That code does this in createShape:

return ShapeFactory.factories[id].create()

So just do this:

myShape = ShapeFactory.factories[id].create()
myShape.foo = foo
return myShape

However, looking at the example on the page you linked to, I can't say I'd recommend that approach at all. The design described in that example is very awkward.