Vladimir

I should have been more clear: the specific scenario I had in mind was using cache as a means to avoid hitting a database. This may become clear in my next post. =)

Good post. :)

Your article is still on target, though, let me emphasize that. Nothing is ever a panacea that cures everything.

I ran into that problem a long time ago. It’s quite a Python wart. I don’t remember all the details, but basically the property is bound to the class it was created in and isn’t overriden for you automatically. Here’s the work-around:

class Foo(object):
def get_foo(self):
return ‘foo’

foo = property(lambda self: self.get_foo())

class Bar(Foo):
def get_foo(self):
return ‘bar’

print Foo().foo, Bar().foo

This will print “foo bar” instead of “foo foo” if you used property as you usually do. All we do now is delay the evaluation of self until the property is actually called, so it picks up the correct subclass instead of being bound forever to the class it was instantiated in.
return ‘bar’