This member is added by an implicit conversion from WUnDiEdgeAssoc[N] to
any2stringadd[WUnDiEdgeAssoc[N]] performed by method any2stringadd in scala.Predef.
This member is added by an implicit conversion from WUnDiEdgeAssoc[N] to
StringFormat[WUnDiEdgeAssoc[N]] performed by method StringFormat in scala.Predef.