Arthur wrote:
Trying to handle the sudden change of state of an instance of an object
- a quantum instance
c starts as a Circle instance.
Say, in the course of the manipulation of c its radius approaches
towards infinity, and upon the radius becoming than some Max, I want c
to suddenly think of itself as a Line instance rather than as a Circle
instance.
doable?
hints?
Art
As a sketch:
class Blended(object):
MaxRadius = 123456
def __init__(self, radius):
self._active = Circle(radius=radius)
self._other = Line()
self.radius = radius # Switch to Line if necessary
def __getattr__(self, name):
return getattr(self._active, name)
def __setattr__(self, name, value):
if name[0] == '_':
object.__setattr__(self, name, value)
elif name[0] != 'radius':
return setattr(self, value)
if value self.MaxRadius:
if isinstance(self._active, Line):
self._active, self._other = self._other, self._active
else:
if isinstance(self._active, Circle):
self._active, self._other = self._other, self._active
self._active.radius = value
You could read up on __getattr__, __getattribute__, and friends in
the Language References section 3.3.2:
Customizing attribute access
--Scott David Daniels
[EMAIL PROTECTED]
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