Module trouble [newbie]

[Boris Ozegovic]

Can somebody explaint this to me:

I have module a.py
A = 100
import b
print "A printing"
print "B is %s" % b.B

and module b.py
B = 2000
import a
print "B printing"
print "A is %s" % a.A

I thought that output would be:
B printing
A is 100
A printing
B is 2000

Because import b would execute b.py, and in b.py line "import a" would be
ignored, but my output is:
100
A printing
B is 100

??

 

[Diez B. Roggisch]

Can somebody explaint this to me:

I have module a.py
A = 100
import b
print "A printing"
print "B is %s" % b.B

and module b.py
B = 2000
import a
print "B printing"
print "A is %s" % a.A

I thought that output would be:
B printing
A is 100
A printing
B is 2000

Because import b would execute b.py, and in b.py line "import a" would be
ignored, but my output is:

100
A printing
B is 100

Are you sure the above is what you really used for your test? Because your
output features a single 100, which the above lacks a print-statement for.


Diez

 

[Boris Ozegovic]

Are you sure the above is what you really used for your test? Because your
output features a single 100, which the above lacks a print-statement for.

Yeah, I cancelled the message, but synchronization allready happened.

Problem was in some other place.

One more question: is calling import inside function definition poor
design? e.g.

def foo():
doSomething:
import someModule
someModule.doSomethin

 

[Diez B. Roggisch]

Yeah, I cancelled the message, but synchronization allready happened.

Problem was in some other place.

One more question: is calling import inside function definition poor
design? e.g.

def foo():
doSomething:
import someModule
someModule.doSomethin

I use it sometimes myself, to avoid otherwise circular imports. However, I
don't like it very much. Try to go without it I'd say, but that is just a
gut-feeling.

Diez

 

[Boris Ozegovic]

I use it sometimes myself, to avoid otherwise circular imports.

Circular imports are the reason why I have module issues. Last question:
if I put modules in some package and then try to import one I get
"AttributeError: 'module' object has no attribute 'a'

Code is:

a.py
A = 756
import someFolder.b as b
print "A printing"
print "B is %s" % b.B

b.py
B = 2000
import someFolder.a as a
print "B printing"
print "A is %s" % a.A

How can I do circular imports if I use packages? Darn. I don't remeber
this module gothcas when reading Learning Python.

 

[Goldfish]

Can somebody explaint this to me:

I have module a.py
A = 100
import b
print "A printing"
print "B is %s" % b.B

and module b.py
B = 2000
import a
print "B printing"
print "A is %s" % a.A

I thought that output would be:
B printing
A is 100
A printing
B is 2000

Because import b would execute b.py, and in b.py line "import a" would be
ignored, but my output is:


100
A printing
B is 100

??



--http://www.nacional.hr/articles/view/23894/23

a.py
=======
A = 100
import b
print "A printing"
print "B is %s" % b.B

b.py
=======
B = 2000
import a
print "B printing"
print "A is %s" % a.A

Python 2.4.4 (#71, Oct 18 2006, 08:34:43) [MSC v.1310 32 bit (Intel)]
on win32
Type "help", "copyright", "credits" or "license" for more information.B printing
A is 100
A printing
B is 2000
Looks okay to me.

 

[Dennis Lee Bieber]

How can I do circular imports if I use packages? Darn. I don't remeber
this module gothcas when reading Learning Python.

Personally -- I wouldn't try...

Move the common items to a third file which both existing files then
import.

Instead of:

a.py
=====
import b
A = xyz
print A, b.B

b.py
====
import a
B = mno
print B, a.A

use

common.py
=========
A = xyz
B = mno

a.py
====
import common
#do stuff

b.py
====
import common
#do stuff
--
Wulfraed Dennis Lee Bieber KD6MOG
(e-mail address removed) (e-mail address removed)
HTTP://wlfraed.home.netcom.com/
(Bestiaria Support Staff: (e-mail address removed))
HTTP://www.bestiaria.com/