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copied!<p>1) <code>fx</code> and <code>john.greet</code> are referring to the same function object, the assignment operation for objects, works <em>by reference</em>.</p> <p>For primitive values, like <code>String</code>, <code>Number</code>, <code>Boolean</code> <code>undefined</code> or <code>null</code>, a copy of the value will be made.</p> <p>2) The <code>this</code> value refers to the global object.</p> <p>The <code>this</code> value is not a property of the <a href="http://bclary.com/2004/11/07/#a-10.1.3" rel="noreferrer">Variable Object</a> and it has nothing to do with the <em>scope chain</em>, is a special reserved word, and it is determined implicitly when a <a href="http://bclary.com/2004/11/07/#a-11.2.3" rel="noreferrer">function is called</a> (you can also set it explicitly via <code>call</code> or <code>apply</code>).</p> <p>JavaScript internally handles a <a href="http://bclary.com/2004/11/07/#a-8.7" rel="noreferrer"><code>Reference type</code></a>, which consists of two components, the <em>base object</em> and the <em>property name</em>, when a function is invoked, the <code>this</code> value is determined implicitly by getting the <em>base object</em> (by the internal <a href="http://bclary.com/2004/11/07/#a-8.7.1" rel="noreferrer"><code>GetValue</code></a> operation).</p> <p>And finally, the last case where <code>this</code> is set implicitly is when you invoke a function with the <a href="http://bclary.com/2004/11/07/#a-11.2.2" rel="noreferrer"><code>new</code></a> operator, the <code>this</code> keyword will refer to a newly created object.</p> <p>So in brief, here is how <code>this</code> works <em>implicitly</em>:</p> <p>1- When a function is called as a method (the function is invoked as member of an object):</p> <pre><code>obj.method(); // 'this' inside method will refer to obj </code></pre> <p>2- A <em>normal</em> function call:</p> <pre><code>myFunction(); // 'this' inside the function will refer to the Global object // or (function () {})(); </code></pre> <p>3- When the <code>new</code> operator is used:</p> <pre><code>var obj = new MyObj(); // 'this' will refer to a newly created object. </code></pre>

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