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vendor/github.com/hashicorp/go-immutable-radix/README.md

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+go-immutable-radix [![Build Status](https://travis-ci.org/hashicorp/go-immutable-radix.png)](https://travis-ci.org/hashicorp/go-immutable-radix)
+=========
+
+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")
+}
+```
+