type DirectedAcyclicGraph … func NewDirectedAcyclicGraph(self, absent float64) *DirectedAcyclicGraph { … } func (g *DirectedAcyclicGraph) HasEdgeFromTo(u, v graph.Node) bool { … } func (g *DirectedAcyclicGraph) From(n graph.Node) []graph.Node { … } func (g *DirectedAcyclicGraph) VisitFrom(n graph.Node, visitor func(neighbor graph.Node) (shouldContinue bool)) { … } func (g *DirectedAcyclicGraph) To(n graph.Node) []graph.Node { … } func (g *DirectedAcyclicGraph) VisitTo(n graph.Node, visitor func(neighbor graph.Node) (shouldContinue bool)) { … }