@User: When describing rules, it is sometimes necessary to limit the rule to a specific plane, namely where contacts are involved, since contact types can exist on more than one plane. Everything else exists only on one plane. So

lic/m1

is

lic

checked only on the

m1

plane, while

lic/li

is

lic

checked only on the

li

plane.

lic

by itself would be checked on both planes. Even I am a bit unsure when it is necessary to limit a rule to a single plane; sometimes it's necessary, sometimes it just prevents the rule from being checked twice, redundantly. Unfortunately it can get quite complicated, with expressions like

~(a,b,c)/p

.

Thanks, now it makes sense