What are the differences between _weak_ references and "normal" references?

[Gerhard Häring]

sdieselil <sdieselil at yahoo.com> wrote:
> Hi
> 
> I noticed a module weakref in Python standard library. What is weak
> reference and in what way it differs from "normal" reference?

Not that I fully understand it myself, but have you looked into the module
documentation for weakref and/or http://www.python.org/peps/pep-0205.html
yet?

>By the way, how can I implement usual reference in Python (I mean C++
>reference)?

::ASSIGN REFERENCE::

C++:

    Foo foo1("foo1");
    Foo& foo2 = foo1;

Python:

    foo1 = Foo("foo1")
    foo2 = foo1

::COPY VALUE::

C++:

    Foo foo1("foo1")
    Foo foo2 = foo1;    // call copy constructor

Python:

    import copy
    foo1 = Foo("foo1")
    foo2 = copy.copy(foo1)

I'm currently re-learning C++, so there may be bugs in the above C++ :-)

-- Gerhard