1 files changed, 66 insertions, 0 deletions
diff --git a/vendor/github.com/hashicorp/go-immutable-radix/README.md b/vendor/github.com/hashicorp/go-immutable-radix/README.md
new file mode 100644
index 0000000..aca15a6
--- /dev/null
+++ b/vendor/github.com/hashicorp/go-immutable-radix/README.md
@@ -0,0 +1,66 @@
+go-immutable-radix [![CircleCI](https://circleci.com/gh/hashicorp/go-immutable-radix/tree/master.svg?style=svg)](https://circleci.com/gh/hashicorp/go-immutable-radix/tree/master)
+=========
+
+Provides the `iradix` package that implements an immutable [radix tree](http://en.wikipedia.org/wiki/Radix_tree).
+The package only provides a single `Tree` implementation, optimized for sparse nodes.
+
+As a radix tree, it provides the following:
+ * O(k) operations. In many cases, this can be faster than a hash table since
+   the hash function is an O(k) operation, and hash tables have very poor cache locality.
+ * Minimum / Maximum value lookups
+ * Ordered iteration
+
+A tree supports using a transaction to batch multiple updates (insert, delete)
+in a more efficient manner than performing each operation one at a time.
+
+For a mutable variant, see [go-radix](https://github.com/armon/go-radix).
+
+Documentation
+=============
+
+The full documentation is available on [Godoc](http://godoc.org/github.com/hashicorp/go-immutable-radix).
+
+Example
+=======
+
+Below is a simple example of usage
+
+```go
+// Create a tree
+r := iradix.New()
+r, _, _ = r.Insert([]byte("foo"), 1)
+r, _, _ = r.Insert([]byte("bar"), 2)
+r, _, _ = r.Insert([]byte("foobar"), 2)
+
+// Find the longest prefix match
+m, _, _ := r.Root().LongestPrefix([]byte("foozip"))
+if string(m) != "foo" {
+    panic("should be foo")
+}
+```
+
+Here is an example of performing a range scan of the keys.
+
+```go
+// Create a tree
+r := iradix.New()
+r, _, _ = r.Insert([]byte("001"), 1)
+r, _, _ = r.Insert([]byte("002"), 2)
+r, _, _ = r.Insert([]byte("005"), 5)
+r, _, _ = r.Insert([]byte("010"), 10)
+r, _, _ = r.Insert([]byte("100"), 10)
+
+// Range scan over the keys that sort lexicographically between [003, 050)
+it := r.Root().Iterator()
+it.SeekLowerBound([]byte("003"))
+for key, _, ok := it.Next(); ok; key, _, ok = it.Next() {
+  if key >= "050" {
+      break
+  }
+  fmt.Println(key)
+}
+// Output:
+//  005
+//  010
+```
+