(innerNodeParam: OuterNode[InnerNodeParam[NI]]).isDefined
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).isEdge
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).isIn
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).isNode
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).isOut
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).stringPrefix
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).toString()
(innerNodeParam: OuterNode[InnerNodeParam[NI]]).value
the type of the nodes (vertices) this graph is passed to by the user.