pub fn ancestors<'a>(&'a self, event: EventRef<'a, N>) -> AncestorIter<'a, N> {
        AncestorIter {
            graph: self,
            queue: iter::once(event).collect(),
        }
    }
/// Gets all the ancestors of an event in the graph.
Gets all the ancestors of an event in the graph.
Gets all the ancestors of an event in the graph .
pub fn ancestors<'a>(&'a self, event: EventRef<'a, N>) -> AncestorIter<'a, N> {
        AncestorIter {
            graph: self,
            queue: iter::once(event).collect(),
        }
    }
pub fn ancestors < ' a > ( & ' a self , event : EventRef < ' a , N > ) -> AncestorIter < ' a , N > { AncestorIter { graph : self , queue : iter :: once ( event ) . collect ( ) , } }
Gets all the ancestors of an event in the graph.
Gets all the ancestors of an event in the graph .
&'a self
event
EventRef<'a, N>