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data strucutures in python

Jeff Petkau jpet at eskimo.com
Thu Sep 21 01:42:04 EDT 2000 
Kragen Sitaker <kragen at dnaco.net> wrote in message
news:jlWx5.448$mc3.45617 at news-east.usenetserver.com...
> I was chatting with a coworker about this today.  He mentioned that C#
> has a neat way of declaring active properties --- you say something
> like:
>
> class foo {
>   property lambda {
>     int get() { code here }
>     void set() { code here }
>   };
> };
>
> and then the code in the get and set "methods" will be invoked to
> implement reading or writing the property "lambda" of any object of the
> class "foo".

How about this:

# evil_things.py ---------------
def magic_getattr(self,name):
    return getattr(self,'get'+name)()

def magic_setattr(self,name,value):
    return apply(getattr(self,'set'+name),(value,))
#------------------------------

# test.py -------------------
# See how those evil things work
import evil_things
class C:
    def getX(self):
        return 3
    def setX(self,value):
        print "ha! still 3"
    __getattr__ = evil_things.magic_getattr
    __setattr__ = evil_things.magic_setattr

# now C has properties!
c = C()
c.X = 20
--> ha! still 3
print c.X
--> 3

ps. Don't try this at home.
--Jeff (jpet at eskimo.com)
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