variable scoping across imports?

[Roy Mathew]

"Fredrik Lundh" <fredrik at pythonware.com> wrote in message > more here:
> ...
>     http://effbot.org/guides/import-confusion.htm
> 
> </F>



Folks,

Thanks for the responses; Fredrik Lundh's response was the most
helpful. From the URL resource he references, I realized that there
are actually 3 imports going on, and not just 2 as one would initially
assume. They are:

  "x.py" as __main__ 
  "x.py" as x
  "y.py" as y

Hence, there really are 2 "z0" variables alive; one belonging
to the __main__ namespace and the other belonging to the "x"
namespace. Thanks for the nice clear explanation, Fredrik.

By rearranging things thus, I am able to get what I expected.
Incidentally the whole motivation for this scheme was to 
simulate "class" variables - ie: have "z0" act as a static
variable.


# ------ file x.py ------------------------------------------------
z0 = None
import y

def set():
    global z0
    z0 = 33

# ------ file y.py ------------------------------------------------
import x

def show():
    print x.z0


# ------ file z.py ------------------------------------------------
import x, y

y.show()
x.set()
y.show()

# -----------------------------------------------------------------

Now, running "python z.py" yields what I had wanted.

Thanks,
Roy Mathew.