import models/SimpleClassDiagrams as SCD
include "primitives.alh"

SCD PetriNets{
    SimpleAttribute Natural {
        constraint =
            $
            String function constraint_Natural(model : Element, name : String):
                Element self
                self = model["model"][name]
                if (is_physical_int(self)):
                    if (integer_gte(self, 0)):
                        return "OK"!
                    else:
                        return "Natural number not larger than or equal to zero"!
                else:
                    return "Natural number not larger than or equal to zero"!
            $
    }

    Class Place{
        tokens : Natural
    }

    Class Transition{}

    Association P2T (Place, Transition) {
        weight : Natural
    }

    Association T2P (Transition, Place) {
        weight : Natural
    }
}

export PetriNets to models/PetriNets