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    <p>Yes it's possible to define privileged methods outside of the constructor. Here is how to do it:</p> <pre><code>var Keeper = (function (key) { function Keeper(get) { var private = { secretPower: "wisdom" }; this.getPrivate = function (k) { if (k === key) return private; }; this.get = get || defaultGet; } function defaultGet() { var private = this.getPrivate(key); return "The secret power is: " + private.secretPower; } return Keeper; }({})); </code></pre> <p>Here is how it works:</p> <ol> <li>We create a namespace by creating an <a href="http://benalman.com/news/2010/11/immediately-invoked-function-expression/" rel="nofollow" title="Ben Alman &raquo; Immediately-Invoked Function Expression (IIFE)">Immediately Invoked Function Expression (IIFE)</a>.</li> <li>We create a object called <code>key</code>. This object is private to the namespace we just created. Hence only privileged functions and the constructor can access it.</li> <li>Inside the constructor we create an object called <code>private</code> which holds the private state of each instance.</li> <li>We also create a privileged method called <code>getPrivate</code> which takes an argument <code>k</code> and only returns the private object if <code>k</code> is the <code>key</code> we created in step 2. Hence only privileged functions can access the private object.</li> <li>Privileged functions which want to access the private state of the object must call <code>getPrivate(key)</code> to get the private state object.</li> </ol> <p><strong>Note:</strong> This method is only useful if you have more than one privileged function which needs to access the private state of the object. In addition the call the <code>getPrivate</code> introduces a (very) small performance overhead to privileged functions.</p> <hr> <p>BTW if you want to write clean object-oriented code in JavaScript then take a look at the <a href="https://github.com/javascript/augment" rel="nofollow" title="javascript/augment"><code>augment</code></a> library. The above code will looks like this using <code>augment</code>:</p> <pre><code>var Keeper = Object.augment(function (key) { this.constructor = function (get) { var private = { secretPower: "wisdom" }; this.getPrivate = function (k) { if (k === key) return private; }; this.get = get || defaultGet; }; function defaultGet() { var private = this.getPrivate(key); return "The secret power is: " + private.secretPower; } }, {}); </code></pre>
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    1. POIs it possible to define priviledge method outside of the constructor?
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    1. USAadit M Shah
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    1. POIs it possible to define priviledge method outside of the constructor?
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    1. COThank you for the answer. Anyway, I have a question: Create new instance of the Keeper and pass function as an argument. Try to return secretPower with that function. It is possible only if you create instance inside of namespace. I understand that defaultGet is priviledge function that is made outside of the constructor. Anyway, it is still binded to namespace... which almoast implicate that it is inside of the constructor.
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    2. CO@Windkiller No. There's only one instance of `defaultGet` which is shared amongst all instances of `Keeper`.
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