Thanks for this insight into classes. It often takes me a few days to absorb and respond because my job limits the time I can give to programming. But thanks again for taking the time to respond in a meaningful way.
I guess I could say that you changed my world when it comes to programming (sorry, low-hanging fruit :))
Luke
On 10/20/05, Danny Yoo <[EMAIL PROTECTED]> wrote:
> Also, I have done what I'm trying to do successfully by populating a
> dictionary with class instances named after self.name <http://self.name>,
> which, after the function runs, I can access this way
> >>> classDictionary["Yard"]
> <class instance>
> the thing is I would like to be able to get at Yard's attributes by typing
> >>> Yard.anAttribute
> garbage cans
> at the prompt rather than
> >>> Yard = classDictionary["Yard"]
> >>> Yard.anAttribute
> garbage cans
Hi Luke,
One thing to note is that we can formally plunk and embed these places in
some kind of World:
######################################################
class World:
def __init__(self):
self.places = {}
def attach(self, place):
"""Given a place, attaches it to the world."""
self.places[ place.name] = place
def lookup(self, name):
return self.places[name]
######################################################
If each place was aware that it was a part of a world --- that is, if we
embed the World inside each place as a part of a place's state --- then
things might work out.
For example, we might have a north-south corridor:
##################################################################
class Corridor:
def __init__(self, world, name, northName, southName):
self.world, self.name, self.northName, self.southName = (
world, name, northName, southName)
def N(self):
return self.world.lookup(self.northName)
def S(self):
return self.world.lookup(self.southName)
##################################################################
What's a little funny about this Corridor definition is that, because a
cooridor knows its in the world, it can also ask the world what place
'northName' stands for in its N() method.
Here's a small test:
######
>>> world = World()
>>> world.attach (Corridor(world, "Water cooler",
... north="Stairs", south="Boss Office"))
>>> world.attach(Corridor(world, "Stairs",
... north="Wall", south="Water cooler"))
>>>
>>>
>>> world.lookup("Water cooler")
<__main__.Corridor instance at 0x403a7fcc>
>>> world.lookup("Water cooler").name
'Water cooler'
>>> world.lookup("Water cooler").N()
<__main__.Corridor instance at 0x403a7f6c>
>>> world.lookup("Water cooler").N().name
'Stairs'
######
Another advantage of having a central place is that saving and restoring
the environment is just a matter of pickling the world. Hmmm... briny
pickles... *grin* Sorry, I'm getting distracted by food.
Does this make sense? Please feel free to ask more questions.
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