From 2b797ef4dc4c0311df3f1a3095ea77f00ab96f58 Mon Sep 17 00:00:00 2001
From: Jian Han <jian.han@neds.com>
Date: Thu, 9 Nov 2017 20:22:11 +1000
Subject: [PATCH] added singleton pattern

---
 creational/main.go                | 12 ++++++++++++
 creational/singleton/singleton.go | 23 +++++++++++++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 creational/main.go
 create mode 100644 creational/singleton/singleton.go

diff --git a/creational/main.go b/creational/main.go
new file mode 100644
index 0000000..e87e110
--- /dev/null
+++ b/creational/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/jianhan/go-patterns/creational/singleton"
+)
+
+func main() {
+	instance := singleton.GetInstance()
+	fmt.Println(instance.AddOne())
+}
diff --git a/creational/singleton/singleton.go b/creational/singleton/singleton.go
new file mode 100644
index 0000000..96afe26
--- /dev/null
+++ b/creational/singleton/singleton.go
@@ -0,0 +1,23 @@
+package singleton
+
+type Singleton interface {
+	AddOne() int
+}
+
+type singleton struct {
+	count int
+}
+
+func (s *singleton) AddOne() int {
+	s.count++
+	return s.count
+}
+
+var instance *singleton
+
+func GetInstance() Singleton {
+	if instance == nil {
+		instance = new(singleton)
+	}
+	return instance
+}