Add decorator pattern

decorator.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+	"log"
+)
+
+func LogDecorate(fn func(s string)) func(s string) {
+	return func(s string) {
+		log.Println("Starting the execution with the argument", s)
+		fn(s)
+		log.Println("Execution is completed.")
+	}
+}
+
+func Function(s string) {
+	fmt.Println(s)
+}
+
+func main() {
+	f := LogDecorate(Function)
+
+	f("Hello Decorator")
+}