I'm experimenting a little bit with MPS regarding testing languages. In doing so, I intend to in the beginning create a simple language allowing me to define Testcases and Testsuites, whereas the latter ones must contain at least one Testcase and may contain other Testsuites. For now, defining the concepts for the Testcase and the Testsuite and also its according editors worked smoothly. However, as already mentioned, my Testsuites may reference other Testsuites, yet, not itself. So right now, I'm stuck at defining some kind of constraint on the TestsuiteReference concept (built according to the Calculator tutorial's InputFieldReference) or a filter in the Testsuite's editor (applied on a horizontal child node cell list), sorting out the very Testsuite and thereby preventing self references. Maybe anyone can give me a hint on how to do that, I hope my explanations suffice for understanding, otherwise just please let me know.
Thanks in advance,