Circular import problem

I'm going quite nutty here with an import problem. I've got a fairly
complicated program (about 12,000 lines in 34 modules). I just made
some "improvements" and get the following error:

bob$ mma
Traceback (most recent call last):
File "/usr/local/bin/mma", line 55, in <module>
import MMA.main
File "/usr/local/share/mma/MMA/main.py", line 33, in <module>
import MMA.docs
File "/usr/local/share/mma/MMA/docs.py", line 34, in <module>
import MMA.grooves
File "/usr/local/share/mma/MMA/grooves.py", line 41, in <module>
import MMA.auto
File "/usr/local/share/mma/MMA/auto.py", line 35, in <module>
import MMA.parse
File "/usr/local/share/mma/MMA/parse.py", line 2052, in <module>
'AUTHOR': MMA.docs.docAuthor,
AttributeError: 'module' object has no attribute 'docs'

I can fix this by deleting a line in docs.py. Just take out the
"import MMA.grooves" and all works. What I really don't get is that in
the middle of this module which is now NOT loading "grooves.py" I have
a command to access a function in that module and it works.

Yes, grooves.py has an import docs.py. And there are lots of other
such imports in the program.

So, I have to assume that the error is being generated by some other
modules loading in the grooves.py stuff ... but really have no idea.

Is there anything I can do to trace though this and get it working
properly?

Seehttp://effbot.org/zone/import-confusion.htm
Try to move the circular references later in the code (maybe inside a
function, when it is required), or much better, refactor it so there is no
circularity.

--
Gabriel Genellina

>

>Seehttp://effbot.org/zone/import-confusion.htm
Try to move the circular references later in the code (maybe inside a
function, when it is required), or much better, refactor it so there is
no
circularity.

--
Gabriel Genellina

Yes, thanks. I'd read that page before posting. Helpful.

But, I still don't understand how python can access a function in a
file I have NOT included. In this case, to get things to work, I DO
NOT "import MMA.grooves" but later in the module I access a function
with "xx=MMA.grooves.somefunc()" and it finds the function, and works
just fine. It shouldn't work.

I have tried to delay the import, and that does work. But, from a
stylistic view I really to like to have all my imports at the top of
the module. Maybe some old assembler/C habits on my part.

before I moved other
imports around I was able to do the following:

1. NOT include MMA.gooves,
2. call the function MMA.grooves.somefunc()

and have it work.

But, I still don't understand how python can access a function in a
file I have NOT included. In this case, to get things to work, I DO
NOT "import MMA.grooves" but later in the module I access a function
with "xx=MMA.grooves.somefunc()" and it finds the function, and works
just fine. It shouldn't work.

I've just used an empty __init__.py file. I will have to read up a bit
more on packages and see what advantage there is to import in that.

Which is considered good style? Loading at the top or loading when
needed?

En Fri, 13 Jul 2007 13:24:57 -0300, bvdp <b...@mellowood.caescribió:

Seehttp://effbot.org/zone/import-confusion.htm
Try to move the circular references later in the code (maybe inside a
function, when it is required), or much better, refactor it so there is
no
circularity.

--
Gabriel Genellina

Yes, thanks. I'd read that page before posting. Helpful.

But, I still don't understand how python can access a function in a
file I have NOT included. In this case, to get things to work, I DO
NOT "import MMA.grooves" but later in the module I access a function
with "xx=MMA.grooves.somefunc()" and it finds the function, and works
just fine. It shouldn't work.

That depends a bit on what is "MMA" and what is "grooves".
MMA.grooves means "look for an attribute named grooves inside MMA". If MMA
is a module, and MMA.grooves is a class/function defined inside the
module, you don't need to import it before using it.

But if MMA is a package, and MMA.grooves is a module inside that package,
you need to import it first (unless MMA/__init__.py does that already)

I have tried to delay the import, and that does work. But, from a
stylistic view I really to like to have all my imports at the top of
the module. Maybe some old assembler/C habits on my part.

Sure, it's considered good style.

--
Gabriel Genellina