1 files changed, 29 insertions, 0 deletions
diff --git a/content/maps/list.go b/content/maps/list.go
new file mode 100644
index 0000000..02bea2c
--- /dev/null
+++ b/content/maps/list.go
@@ -0,0 +1,29 @@
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build OMIT
+
+package main
+
+import "fmt"
+
+func main() {
+	// START OMIT
+	type Node struct {
+		Next  *Node
+		Value interface{}
+	}
+	var first *Node
+
+	visited := make(map[*Node]bool) // HL
+	for n := first; n != nil; n = n.Next {
+		if visited[n] { // HL
+			fmt.Println("cycle detected")
+			break
+		}
+		visited[n] = true // HL
+		fmt.Println(n.Value)
+	}
+	// END OMIT
+}