chore: add generic example of ordered map

orderedmap/example/generic/main.go

@@ -0,0 +1,94 @@
+//go:build go1.21
+// +build go1.21
+
+package main
+
+import (
+	"fmt"
+
+	"github.com/fufuok/utils/orderedmap"
+)
+
+func main() {
+	om := orderedmap.NewOf[int]()
+	om.Set("a", 1)
+	om.Set("b", 2)
+	om.Sort(func(a *orderedmap.PairOf[int], b *orderedmap.PairOf[int]) bool {
+		return a.Value() > b.Value()
+	})
+	for _, k := range om.Keys() {
+		v := om.MustGet(k)
+		fmt.Println(k, v)
+	}
+
+	c := om.Clone()
+	m := om.ToMap()
+	_ = c
+	_ = m
+
+	// use NewOf[any]() instead of o := map[string]any{}
+	o := orderedmap.NewOf[any]()
+
+	// use Set instead of o["a"] = 1
+	o.Set("a", 1)
+	o.Set("c", 2)
+
+	// add some value with special characters
+	o.Set("b", "\\.<>[]{}_-")
+
+	// use Get instead of i, ok := o["a"]
+	val, ok := o.Get("a")
+	fmt.Println("Get:", val, ok)
+
+	// use Keys instead of for k, v := range o
+	keys := o.Keys()
+	for _, k := range keys {
+		v, _ := o.Get(k)
+		fmt.Println(k, v)
+	}
+
+	// use o.Delete instead of delete(o, key)
+	o.Delete("b")
+
+	fmt.Println("sort the keys:")
+	o.SortKeys()
+	for _, k := range o.Keys() {
+		v, _ := o.Get(k)
+		fmt.Println(k, v)
+	}
+
+	fmt.Println("sort by Pair:")
+	o.Sort(func(a *orderedmap.PairOf[any], b *orderedmap.PairOf[any]) bool {
+		return a.Value().(int) < b.Value().(int)
+	})
+	for _, k := range o.Keys() {
+		v, _ := o.Get(k)
+		fmt.Println(k, v)
+	}
+
+	fmt.Println("sort by Pair(reverse):")
+	o.Sort(func(a *orderedmap.PairOf[any], b *orderedmap.PairOf[any]) bool {
+		return a.Value().(int) > b.Value().(int)
+	})
+	for _, k := range o.Keys() {
+		v, _ := o.Get(k)
+		fmt.Println(k, v)
+	}
+}
+
+// Output:
+// b 2
+// a 1
+// Get: 1 true
+// a 1
+// c 2
+// b \.<>[]{}_-
+// sort the keys:
+// a 1
+// c 2
+// sort by Pair:
+// a 1
+// c 2
+// sort by Pair(reverse):
+// c 2
+// a 1