Merge pull request torokmark#13 from rugpanov/master

Improve SingletonPattern example

singleton/demo.ts

@@ -3,8 +3,8 @@ namespace SingletonPattern {
 	export namespace Demo {
 
 		export function show() : void {
-			var singleton1 = SingletonPattern.Singleton.Instance();
-			var singleton2 = SingletonPattern.Singleton.Instance();
+			const singleton1 = SingletonPattern.Singleton.getInstance();
+			const singleton2 = SingletonPattern.Singleton.getInstance();
 
 			if (singleton1 === singleton2) {
 				console.log("two singletons are equivalent");

singleton/singleton.ts

@@ -1,21 +1,23 @@
 namespace SingletonPattern {
     export class Singleton {
-        // A variable which stores the singleton object. Intially,
+        // A variable which stores the singleton object. Initially,
         // the variable acts like a placeholder
-        private static singleton: Singleton = null;
+        private static singleton: Singleton;
+
         // private constructor so that no instance is created
         private constructor() {
         }
+
         // This is how we create a singleton object
-        public static Instance(): Singleton {
+        public static getInstance(): Singleton {
             // check if an instance of the class is already created
-            if (this.singleton == null) {
+            if (!Singleton.singleton) {
                 // If not created create an instance of the class
                 // store the instance in the variable
-                this.singleton = new Singleton();
+                Singleton.singleton = new Singleton();
             }
             // return the singleton object
-            return this.singleton
+            return Singleton.singleton;
         }
     }
 }