[Swig-devel] [ swig-Bugs-3331170 ] side effect between classes

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Bugs item #3331170, was opened at 2011-06-25 14:40
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Category: python
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: David Froger (dfroger)
Assigned to: Nobody/Anonymous (nobody)
Summary: side effect between classes

Initial Comment:
Hi,

I observe some side effect when instantiating two C++ class from Python and
making them working together is a particular manner.

There are files attached to reproduce the problem. However, because it is about
memory allocation, I'm not sure the behaviour will be the same as I observe...

Compiling and running in pure C++:
make cpp
make testcpp

I get this ouput:
_the_set: 1 5
_the_set: 1 5

But using Swig:
make py
make testpy

I get this ouptut, showing that writting into "another_set" also write, by side
effect, into  "_the_set":
_the_set: 1 5
_the_set: 1 222

SWIG Version 1.3.36
Linux ange 2.6.31-22-generic #73-Ubuntu SMP Fri Feb 11 19:18:05 UTC 2011 x86_64 GNU/Linux

Best,

David


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Comment By: https://www.google.com/accounts ()
Date: 2011-06-27 12:09

Message:
Ok,  this was not a bug... The good main.py is :

a = ab.A()
b = ab.B()
b.thisown = 0
a.set_b( b )
a.dosomething()

And the documentation explains it very well:
http://swig.org/Doc2.0/Python.html#Python_nn30

:-)

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=101645&aid=3331170&group_id=1645