[PyQt] [SIP] How to reasonably implement writable global variables?

[Casper Ti. Vector]

[Mistakenly sent to the author instead of the mail list, now re-sent.
Plus, perhaps Phil can set the `Reply-To:' flag in the configuration of
the mail list program so that replies are by default sent to the list?]

Again, I found that static members of classes are read-only when used
from the class directly, for example:

test.h:
> struct test { static int x; };
> extern test Test;
> int get();
> void set(int x);

test.cpp:
> #include "test.h"
> int test::x = 0;
> test Test;
> int get() { return Test.x; }
> void set(int x) { Test.x = x; }

test.sip:
> %Module test
> %ModuleHeaderCode
> #include "test.h"
> %End
> struct test { static int x; };
> test Test;
> int get();
> void set(int x);

test.py:
> import test
> test.get()        # prints 0
> test.test.x       # also prints 0
> test.Test.x       # also prints 0
>
> test.set(1)       # set using set function
> test.test.x       # prints 1, so the [C++ -> python] data transfer
>                   # succeeded.
>
> test.Test.x = 2   # set using instance of class
> test.get()        # prints 2, so the [python -> C++] data transfer
>                   # succeeded.
>
> test.test.x = 3   # set using the class directly
> test.get()        # prints 2, so the [python -> C++] data transfer
>                   # failed.
> test.Test.x       # prints 3, so `x' in the `test' class does not
>                   # refer to its former C++ counterpart now.

So is there a way to make the modifications via uninstantiated classe to
static members available to their C++ counterparts?  Thanks very much :)

On Wed, Jul 03, 2013 at 09:30:29AM +0100, Phil Thompson wrote:
> You can't do it. Python needs to support module level descriptors for it
> to be implemented.

-- 
My current OpenPGP key:
4096R/0xE18262B5D9BF213A (expires: 2017.1.1)
D69C 1828 2BF2 755D C383 D7B2 E182 62B5 D9BF 213A