Pass by reference or by value?

Erik Max Francis max at
Sat Jul 14 00:26:13 CEST 2007

James Stroud wrote:

> Robert Dailey wrote:
>> I noticed in Python all function parameters seem to be passed by
>> reference. This means that when I modify the value of a variable of a
>> function, the value of the variable externally from the function is
>> also modified.
>> Sometimes I wish to work with "copies", in that when I pass in an
>> integer variable into a function, I want the function to be modifying
>> a COPY, not the reference. Is this possible?
> Not only is this possible, that is actually what happens with ints!

But that's because ints are immutable, not because there is an explicit 
copy of anything being made.

Erik Max Francis && max at &&
  San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
   Ipsa scientia potestas est. "Knowledge itself is power."
    -- a Latin proverb

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