Preventing Circular References in Modules

ramensaurus has asked for the wisdom of the Perl Monks concerning the following question:

Hi everyone,

I have two potentially basic questions about packages and scoping. I am self taught so I think that there may be a chance that there is something basic I'm not understanding here that can clear this up immediately. I have two different Perl modules, let's say package A and B.

Let's say that Package A uses Package B. However, as things become more complex, we find out that Package B needs to use some subroutines from Package A as well.

We know that we cannot just put use B; in Package A AND use A; in Package B because that would cause a circular reference. Also, we noticed that package B can call Package A subroutines directly without using use A;. While I can understand that there are package wide variables that can be accessed between the two packages, I don't understand how package B can call package A subroutines without using use A;

So the questions are:

1) What is the proper way to have package A and package B use each others subroutines without causing a circular reference?

2) Why is it that package B can use package A subroutines without using use A;

Let me know if more details are needed on my question - I hope that was clear.

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Re: Preventing Circular References in Modules by GotToBTru (Prior) on Sep 16, 2015 at 20:19 UTC
Using Super Search for the term circular for instance, shows stuff like this. Dum Spiro Spero	[reply]
Re^2: Preventing Circular References in Modules by Anonymous Monk on Sep 16, 2015 at 23:23 UTC
or searching ... my memory ... finds Re^3: Behaviour on recursive use	[reply]
Re: Preventing Circular References in Modules by Anonymous Monk on Sep 16, 2015 at 19:55 UTC
We know that we cannot just put `use B;` in Package A AND `use A;` in Package B In general, that is incorrect. Read more... (758 Bytes) Why is it that package B can use package A subroutines without using `use A;` Maybe because the subroutines are getting pulled into B in some other way? Both of your questions are unclear without some short sample code that reproduces the issue.	[reply] [d/l] [select]