Modifying Class Object
Alf P. Steinbach
alfps at start.no
Tue Feb 9 05:01:16 CET 2010
* Stephen Hansen -> Alf P. Steinbach:
> To say, "pass by value" implies things to people. It describes a sort of
> world where I'm a function about to do some work, and on my desk I have
> a series of boxes with names on it. It describes an environment where
> someone comes over and drops something into each of my boxes. The
> contents of these boxes are mine alone!
Then, when the imprecision makes people misunderstand, one should not say that.
One should then be more precise.
One should say /what/ is passed by value.
> >>> import copy
> >>> def doit(a):
> ... a += a
> ... return a
> >>> test1 = 1
> >>> test2 = doit(test1)
> >>> test1
> >>> test2
> >>> test3 = 
> >>> test4 = doit(test3)
> >>> test3
> [1, 1]
> >>> test4
> [1, 1]
> I know you already know this, but the point is: you're -hurting- other
> peoples understanding by using terms like this that don't apply to
> Python's specific nature.
The terms apply very well to Java. And Java has the identical parameter passing
mechanism for class type objects. Hence, the argument is bogus.
Cheers & hth.,
PS: I cannot see any of your postings on Usenet. So I just sort of grabbed this
from GMane and posted to Usenet. Hopefully you'll see it back at the list. :-)
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