Add demo to singleton

singleton/src/demo.ts

@@ -0,0 +1,18 @@
+/// <reference path="singleton.ts" />
+namespace SingletonPattern {
+	export namespace Demo {
+
+		export function show() : void {
+			var singleton1 = SingletonPattern.Singleton.Instance;
+			var singleton2 = SingletonPattern.Singleton.Instance;
+
+			if (singleton1 === singleton2) {
+				console.log("two singletons are equivalent");
+			} else {
+				console.log("two singletons are not equivalent");
+			}
+		}
+	}
+}
+
+SingletonPattern.Demo.show();

singleton/src/singleton.ts

@@ -1,14 +1,14 @@
-namespace SingletonPattern {
-    export class Singleton {
-        private static instance: Singleton;
-
-        constructor() {}
-
-        static get Instance() {
-            if (this.instance === null || this.instance === undefined) {
-                this.instance = new Singleton();
-            }
-            return this.instance;
-        }
-    }
-}
+namespace SingletonPattern {
+    export class Singleton {
+        private static instance: Singleton;
+
+        constructor() {}
+
+        static get Instance() {
+            if (this.instance === null || this.instance === undefined) {
+                this.instance = new Singleton();
+            }
+            return this.instance;
+        }
+    }
+}