GlobalSim::BitSpec< Derived, N, Base > Node1 GlobalSim::BitSpec < Derived, N, Base > + width + field() + numFields() + forEachField() + json() + packFields() # makeFields() # allFields() # validateFields() - validateFieldList() - validateField() - checkOverlap() Node2 GlobalSim::NoBase   + allFields() Node2->Node1