Problems USEing matroid in 2.10

[hampe]

I have a problem when trying to include functionality from the application matroid in my extension.

I have a main.rules file for tropical that includes a "USE matroid" clause at the beginning. When I start polymake it complains

Loading applications now...polymake: ERROR: "/home/hampe/work/atint/apps/tropical/rules/main.rules", line 24: rule file /home/hampe/work/atint/apps/matroid/rules/main.rules does not exist

In fact, I don't have any extension to matroid in my extension directory. Even if I do create it via found_extension and add a main.rules file (either empty or containing some dummy functions), polymake now complains upon restart:

Loading applications now...polymake: ERROR: "/usr/local/share/polymake/perllib/Polymake/Core/Application.pm", line 309: Can't call method "so_name" on an undefined value

If I replace USE matroid by any other application, i.e USE fan/ USE polytope, etc., everything works fine (except that I can't call the functions from matroid ). As the subject title suggests, this only happens in 2.10

[gawrilow]

First of all, I'm not lucky about the idea of introducing dependences between applications at the extension level. We should probably constrain the allowed appearances of USE and IMPORT commands to the primary main.rules of each application.

Anyway, in your concrete case you are trying to establish a circular dependence, because application matroid already USEs tropical, even if the reason for the latter remains obscure for me. Recently we have introduced a mechanism allowing to add properties in applications different from the object's "native" one. Perhaps this will help to remove the dependence between matroid and tropical as well.

[hampe]

So, if I understand this correctly: Currently there is no way to use matroid functionality in tropical - but there will be?

[sherrmann]

So, if I understand this correctly: Currently there is no way to use matroid functionality in tropical - but there will be?

There is, it is just not possible to do this via a USE statement in a rule file. For example, one can write scripts in the application tropical using function from the application matroid, or write c++ clients that include files form the application matroid.

[hampe]

Now, if I created a new application instead of an extension, adding dependencies via USE and IMPORT in the main.rules file should be fine?