diff --git a/src/lib.rs b/src/lib.rs
index afd41fc..03610bd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -43,7 +43,7 @@
 //! graph.link_ports(port_a, port_b).unwrap();
 //!
 //! // Run a topological sort on the graph starting at node A.
-//! let topo: TopoSort = toposort(&graph, [node_a], Direction::Outgoing);
+//! let topo: TopoSort<_> = toposort(&graph, [node_a], Direction::Outgoing);
 //! assert_eq!(topo.collect::<Vec<_>>(), [node_a, node_b]);
 //! ```
 //!