TypeCheckerInheritanceTest.java:8: Aspects are not allowed to extend classes because this would imply an ambiguity in the meta level. aspect ExtendsClass extends Clazz {} ^---^ TypeCheckerInheritanceTest.java:11: Super aspect type 'Test1' has meta level 1 while this aspect has meta level 0. The meta levels have to coincide. aspect ExtendsMeta1Aspect extends Test1 {} ^---^ TypeCheckerInheritanceTest.java:14: Super aspect type 'Test' has meta level 0 while this aspect has meta level 1. The meta levels have to coincide. meta aspect ExtendsAspect extends Test {} ^--^ 3 errors.