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copied!<p>It is as Sean says: you aren't actually creating a new reference to an object (creating a <em>this</em> context), because you are simply calling the constructor - not utilizing the constructor to create a new object. If you use the <strong>new</strong> keyword, it works just peachy.</p> <p>Since the scope of <em>test()</em> is <em>window</em> when you call it, any function called from within <em>test()</em> will execute in the <em>window</em> scope. </p> <p>By using the <strong>new</strong> keyword, you are allocating a new object to memory - and creating a new scope.</p> <p>For example, try this in firebug:</p> <pre><code>var myFunction = function() { this.memberVariable = "foo"; console.log(this); } myFunction(); console.log(window.memberVariable); var myObject = new myFunction(); console.log(myObject.memberVariable); </code></pre> <p>You will see this result:</p> <pre><code>Window stats foo Object { memberVariable="foo"} foo </code></pre> <p>The Function base object has a method, <em>call()</em>, which as outlined by Craig, allows you to explicitly specify which scope the function should run in:</p> <pre><code>var myFunction = function() { this.memberVariable = "foo"; } myFunction.call(myFunction); console.log(myFunction); // "Function()" console.log(myFunction.memberVariable); // "foo" </code></pre> <p>This is, however, not the preferred way of doing things, as you aren't actually creating a new object here, and typeof myFunction will still return "function" instead of "object" - when you really just wanted to create an object.</p>

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