add patricia datastructure

Author: mobus

examples/paricia/main.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/sunvim/utils/patricia"
+)
+
+func main() {
+	// Create a new tree.
+	trie := patricia.NewTrie()
+
+	// Insert some items.
+	trie.Insert(patricia.Prefix("Pepa Novak"), 1)
+	trie.Insert(patricia.Prefix("Pepa Sindelar"), 2)
+	trie.Insert(patricia.Prefix("Karel Macha"), 3)
+	trie.Insert(patricia.Prefix("Karel Hynek Macha"), 4)
+
+	// Just check if some things are present in the tree.
+	key := patricia.Prefix("Pepa Novak")
+	fmt.Printf("%q present? %v\n", key, trie.Match(key))
+	key = patricia.Prefix("Karel")
+	fmt.Printf("Anybody called %q here? %v\n", key, trie.MatchSubtree(key))
+
+	// Walk the tree.
+	trie.Visit(printItem)
+	// "Karel Hynek Macha": 4
+	// "Karel Macha": 3
+	// "Pepa Novak": 1
+	// "Pepa Sindelar": 2
+
+	// Walk a subtree.
+	trie.VisitSubtree(patricia.Prefix("Pepa"), printItem)
+	// "Pepa Novak": 1
+	// "Pepa Sindelar": 2
+
+	// Modify an item, then fetch it from the tree.
+	trie.Set(patricia.Prefix("Karel Hynek Macha"), 10)
+	key = patricia.Prefix("Karel Hynek Macha")
+	fmt.Printf("%q: %v\n", key, trie.Get(key))
+	// "Karel Hynek Macha": 10
+
+	// Walk prefixes.
+	prefix := patricia.Prefix("Karel Hynek Macha je kouzelnik")
+	trie.VisitPrefixes(prefix, printItem)
+	// "Karel Hynek Macha": 10
+
+	// Delete some items.
+	trie.Delete(patricia.Prefix("Pepa Novak"))
+	trie.Delete(patricia.Prefix("Karel Macha"))
+
+	// Walk again.
+	trie.Visit(printItem)
+	// "Karel Hynek Macha": 10
+	// "Pepa Sindelar": 2
+
+	// Delete a subtree.
+	trie.DeleteSubtree(patricia.Prefix("Pepa"))
+
+	// Print what is left.
+	trie.Visit(printItem)
+	// "Karel Hynek Macha": 10
+
+}
+
+func printItem(prefix patricia.Prefix, item patricia.Item) error {
+	fmt.Printf("%s  %v\n", prefix, item)
+	return nil
+}