Edit docs for edge_entry()
diff --git a/src/graph.rs b/src/graph.rs
index 2d68af5..e7d217a 100644
--- a/src/graph.rs
+++ b/src/graph.rs
@@ -819,6 +819,9 @@
}
}
+ /// Return an “entry” for the edge from `a` to `b` which is either
+ /// `Vacant` if the edge does not exist, or `Occupied` if at least
+ /// one such edge exists.
pub fn edge_entry(&mut self, a: NodeIndex<Ix>, b: NodeIndex<Ix>)
-> EdgeEntry<N, E, Ix>
{
@@ -1346,6 +1349,7 @@
impl<'a, E, Ix> OccupiedEdgeEntry<'a, E, Ix>
where Ix: IndexType,
{
+ /// Return the index of the edge
pub fn index(&self) -> EdgeIndex<Ix> {
self.index
}
@@ -1396,10 +1400,12 @@
}
}
+ /// Return the index that the edge would use if added.
pub fn index(&self) -> EdgeIndex<Ix> {
edge_index(self.edges.len())
}
+ /// Add the edge using `weight`.
pub fn add_edge(self, weight: E) -> (EdgeIndex<Ix>, &'a mut E) {
let mut edge = Edge {
weight: weight,
@@ -1427,15 +1433,21 @@
}
}
+/// An edge “entry” item.
#[derive(Debug)]
pub enum EdgeEntry<'a, N: 'a, E: 'a, Ix: 'a = DefaultIx> {
+ /// A reference to an existing edge
Occupied(OccupiedEdgeEntry<'a, E, Ix>),
+ /// A representation of an edge that can be added
Vacant(VacantEdgeEntry<'a, N, E, Ix>),
}
impl<'a, N, E, Ix> EdgeEntry<'a, N, E, Ix>
where Ix: IndexType,
{
+ /// If the edge is occupied, add it by using the weight returned
+ /// by `new_weight`; return the index of the edge and a mutable
+ /// reference to the edge weight in either case.
pub fn or_add_edge_with<F>(self, new_weight: F)
-> (EdgeIndex<Ix>, &'a mut E)
where F: FnOnce() -> E,
@@ -1913,6 +1925,41 @@
}
}
+impl<'a, N, E, Ty, Ix> IntoNodeReferences for &'a Graph<N, E, Ty, Ix>
+ where Ty: EdgeType,
+ Ix: IndexType,
+{
+ type NodeRef = (NodeIndex<Ix>, &'a N);
+ type NodeReferences = NodeReferences<'a, N, Ix>;
+ fn node_references(self) -> Self::NodeReferences {
+ NodeReferences {
+ iter: self.nodes.iter().enumerate()
+ }
+ }
+}
+
+/// Iterator over all nodes of a graph.
+pub struct NodeReferences<'a, N: 'a, Ix: IndexType = DefaultIx> {
+ iter: iter::Enumerate<slice::Iter<'a, Node<N, Ix>>>,
+}
+
+impl<'a, N, Ix> Iterator for NodeReferences<'a, N, Ix>
+ where Ix: IndexType
+{
+ type Item = (NodeIndex<Ix>, &'a N);
+
+ fn next(&mut self) -> Option<Self::Item> {
+ self.iter.next().map(|(i, node)|
+ (node_index(i), &node.weight)
+ )
+ }
+
+ fn size_hint(&self) -> (usize, Option<usize>) {
+ self.iter.size_hint()
+ }
+}
+
+
/// Iterator over the edge indices of a graph.
#[derive(Clone, Debug)]
pub struct EdgeIndices<Ix = DefaultIx> {
@@ -1962,40 +2009,6 @@
}
}
-impl<'a, N, E, Ty, Ix> IntoNodeReferences for &'a Graph<N, E, Ty, Ix>
- where Ty: EdgeType,
- Ix: IndexType,
-{
- type NodeRef = (NodeIndex<Ix>, &'a N);
- type NodeReferences = NodeReferences<'a, N, Ix>;
- fn node_references(self) -> Self::NodeReferences {
- NodeReferences {
- iter: self.nodes.iter().enumerate()
- }
- }
-}
-
-/// Iterator over all nodes of a graph.
-pub struct NodeReferences<'a, N: 'a, Ix: IndexType = DefaultIx> {
- iter: iter::Enumerate<slice::Iter<'a, Node<N, Ix>>>,
-}
-
-impl<'a, N, Ix> Iterator for NodeReferences<'a, N, Ix>
- where Ix: IndexType
-{
- type Item = (NodeIndex<Ix>, &'a N);
-
- fn next(&mut self) -> Option<Self::Item> {
- self.iter.next().map(|(i, node)|
- (node_index(i), &node.weight)
- )
- }
-
- fn size_hint(&self) -> (usize, Option<usize>) {
- self.iter.size_hint()
- }
-}
-
impl<'a, Ix, E> EdgeReference<'a, E, Ix>
where Ix: IndexType,
{
