En Tue, 24 Feb 2009 22:52:20 -0200, Ethan Furman <et...@stoneleaf.us>
escribió:
Steve Holden wrote:
Brian Allen Vanderburg II wrote:
One idea to make constants possible would be to extend properties to be
able to exist at the module level as well as the class level:
@property
def pi():
return 3.14159.....
print(pi) # prints 3.14159....
pi=32 # Raise an error Cannot set attribute ...
I don't understand why this would print 3.14159 ... instead of
<function
__math__.pi>, or whatever.
property would clearly have to do something very different in module
scope in order to make this work.
regards
Steve
--> class tester(object):
... @property
... def pi(self):
... return 3.141596
...
--> testee = tester()
--> testee.pi
3.1415959999999998
Looks like that's how property works, so the same behavior on a module
level would do as Brian suggests.
Note that:
- you defined the property inside the *class* tester
- then, you created an *instance* of such class
- you retrieve pi from the instance
- if you retrieve pi from the class (tester.pi), you get a property
object, not a float.
- if you directly attach the property to the instance, testee.pi returns
a property object, not a float.
Finally, consider that modules are instances of type `module`; all modules
are instances of the same type.
How do you propose to make properties work at the module level?
--
Gabriel Genellina
--
http://mail.python.org/mailman/listinfo/python-list
