problems with circular references

[Terry Reedy]

"jimh" <jim at jim.jim> wrote in message
news:a7tbd4$qc7$1 at web1.cup.hp.com...
> I am working on python code that consist of quite a few files (about
50;
> each file contains one class).  All errors returned by functions are
numeric
> and are defined in the individual files.  There is a
MessageCatalog.py class
> which will map these numbers into strings.  This MessageCatalog.py
has to
> import all of the 50 other files to have access to their error
numbers.  So
> far, so good - no problems yet.
>
> Here is the problem: Most of these 50 classes need to use the
MessageCatalog
> themselves.  This means, of course, that classA imports
MessageCatalog which
> imports classA.  This doesn't work very well.
>
> Does anyone have ideas on how to deal with this situation?

I would probably follow the standard Python idiom of using exceptions
instead of numeric error codes, and look at standard library modules
for precedents.

Terry J. Reedy