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copied!<h1>The <code>prototype</code> object</h1> <p>The idea of the <code>prototype</code> object is that it is an object off which all new objects of that type will get their methods and properties off. By adding to the <code>prototype</code> of a predefined object, such as an <code>Array</code> or <code>String</code>, whenever a new object of that type is created, all of the methods and properties you defined to it's <code>prototype</code> will be copied to the new object.</p> <h2>How do I do it?</h2> <p>To do it, you simply follow the notation <code>Object.prototype.myProperty = value</code>, so in your case you want to add a method which converts the entire array of Strings into numbers, here is a simple example of how you would do it:</p> <h3>Example</h3> <pre><code>//So here, you see the definition of your new method //Note the use of the 'Object.prototype.property = value' notation Array.prototype.stringsToNumbers = function() { //I use the Whitesmiths indentation style, get over it :p //To refer to the object which the method was called on use the //'this' keyword. for (index in this) { if (typeof(this[index]) === 'string') //Always typecheck... Always. { this[index] = parseFloat(this[index]); } } //Sometimes you want to return the object to allow for chaining. return this; } //You would then use it like this: var myArray = ["23","11","42"]; myArray.stringsToNumbers(); //myArray now contains [23,11,42] </code></pre> <h2>What else should I be aware of?</h2> <p>Arguably, the largest danger of prototyping native objects is that there creates a chance of collisions with other third party code, especially when extending the native objects with relatively common methods, such as <code>Array.prototype.empty()</code>. Take this into account while prototyping native objects, especially with the naming of your methods and properties. Consider adding a prefix to the method if you believe there is a chance of a collision, so use <code>Array.prototype.mylibEmpty()</code> instead.</p>

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