include "primitives.alh"

SimpleAttribute Natural{
    constraint = $
        String function constraint(model : Element, name : String):
            if (is_physical_int(model["model"][name])):
                return "OK"!
            else:
                return "Natural has non-integer value"!
        $
}

SimpleAttribute String{
    constraint = $
        String function constraint(model : Element, name : String):
            if (is_physical_string(model["model"][name])):
                return "OK"!
            else:
                return "String has non-string value"!
        $
}

SimpleAttribute Boolean {}

Class Named {
    name : String
}
Class Place : Named {
    tokens : Natural
}
Class Transition : Named {}
Class Port : Named {}

Association P2T (Place, Transition) {}
Association T2P (Transition, Place) {}
Association PortPlace (Port, Place) {}
Association Related (Port, Port) {}