Mutual module imports

[Tony Nelson]

How does one normally make a Python extension module that has some parts
in Python and some functions in C share globals between the Python and C
functions? Will that approach work with Pyrex?

I have written a Python module that uses some C functions. I wrote the
module in two parts, one Python, one Pyrex (C). They need to share some
globals. (I use pyrex to handle ref counting. I think I'm glad I did.)

At first they just sort of mutually imported each other, and it worked
until I put tests in the Python one and set it up to run them when it is
named "__main__". What happened reminded me that there are also other
ways modules can be imported under different names, so I tried a
different approach.

Now the Python module imports the Pyrex module and just shoves
references to its globals into the Pyrex module (the Pyrex module
defines them as None). The Pyrex module doesn't import the Python
module anymore. This also works, even when the Python module has a
different name (e.g. "__main__") . I just feel dirty about it.
_______________ _______________ _______________ _______________ ____________
TonyN.:' *firstname*nlsn ews@georgea*las tname*.com
' <http://www.georgeanels on.com/>

[Tuvas]

Re: Mutual module imports

The trick is via something called Extending. Pyrex just makes extending
a bit easier, but, depending on the complexity of the function, it
might be easier just to extend it yourself. Basically you make a
function that translates python into C. There are some instructions on
the Python website, http://www.python.org . Look around, and you'll
find lots of cool stuff on it.

[George Sakkis]

Re: Mutual module imports

"Tony Nelson" <*firstname*nls news@georgea*la stname*.com> wrote:
[color=blue]
> [snipped]
>
> I have written a Python module that uses some C functions. I wrote the
> module in two parts, one Python, one Pyrex (C). They need to share some
> globals.
>[/color]
[color=blue]
> [snipped]
>
> Now the Python module imports the Pyrex module and just shoves
> references to its globals into the Pyrex module (the Pyrex module
> defines them as None). The Pyrex module doesn't import the Python
> module anymore. This also works, even when the Python module has a
> different name (e.g. "__main__") . I just feel dirty about it.[/color]

Well, I feel dirty every time I have to share globals <wink>.

George