Modifying Class Object

Steve Holden steve at holdenweb.com
Mon Feb 8 02:31:31 CET 2010


T wrote:
> Ok, just looking for a sanity check here, or maybe something I'm
> missing.  I have a class Test, for example:
> 
> class Test:
>     def __init__(self, param1, param2, param3):
>         self.param1 = param1
>         self.param2 = param2
>         self.param3 = param3
> 
> Next, I have a dictionary mytest that contains instances of Test.  If
> I want to modify one of the Test instances within my dictionary, I
> have to rewrite the entire entry, correct (since Python passes by
> value, not reference)?  I.e. if I wish to change just param3 of an
> instance, I would have to do:
> 
> def changevalue():
>     for key in mytest.keys():
>         currentparam = mytest[key]
>         param1 = currentparam.param1
>         param2 = currentparam.param2
>         param3 = currentparam.param3
>         param3 = "newvalue"
>         mytest[key] = Test(param1, param2, param3)
> 
> If there's an easier way to accomplish this that I'm missing, that'd
> be great!

def changevalue():
    for key in mytest.keys():
        mytest[key].param3 = "newvalue"

regards
 Steve
-- 
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