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copied!<p>I agree with you, the simplest way is to use a object literal, but if you want <em>private</em> members, you could implement taking advantage of <a href="http://www.jibbering.com/faq/faq_notes/closures.html" rel="nofollow noreferrer">closures</a>:</p> <pre><code>var myInstance = (function() { var privateVar; function privateMethod () { // ... } return { // public interface publicMethod1: function () { // private members can be accessed here }, publicMethod2: function () { // ... } }; })(); </code></pre> <p>About the <code>new function(){}</code> construct, it will simply use an anonymous function as a <a href="https://developer.mozilla.org/En/Core_JavaScript_1.5_Guide/Creating_New_Objects/Using_a_Constructor_Function" rel="nofollow noreferrer"><code>constructor function</code></a>, the context inside that function will be a new object that will be returned.</p> <p><strong>Edit:</strong> In response to the <a href="https://stackoverflow.com/questions/1895635/javascript-singleton-question#comment-1799557">@J5's comment</a>, that is simple to do, actually I think that this can be a nice example for using a <em>Lazy Function Definition</em> pattern:</p> <pre><code>function singleton() { var instance = (function() { var privateVar; function privateMethod () { // ... } return { // public interface publicMethod1: function () { // private members can be accessed here }, publicMethod2: function () { // ... } }; })(); singleton = function () { // re-define the function for subsequent calls return instance; }; return singleton(); // call the new function } </code></pre> <p>When the function is called the first time, I make the object instance, and reassign <code>singleton</code> to a new function which has that object instance in it's closure.</p> <p>Before the end of the first time call I execute the re-defined <code>singleton</code> function that will return the created instance.</p> <p>Following calls to the <code>singleton</code> function will simply return the <code>instance</code> that is stored in it's closure, because the new function is the one that will be executed.</p> <p>You can prove that by comparing the object returned:</p> <pre><code>singleton() == singleton(); // true </code></pre> <p>The <code>==</code> operator for objects will return <code>true</code> only if the object <em>reference</em> of both operands is the same, it will return false even if the objects are identical but they are two different instances:</p> <pre><code>({}) == ({}); // false new Object() == new Object(); // false </code></pre>

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