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