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POJavascript factory pattern variable scoping
 

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    <p>I am following a tutorial that is showing the factory pattern to create objects in javascript. The following code has me stumped as to why it works.</p> <pre><code>&lt;html xmlns="http://www.w3.org/1999/xhtml"&gt; &lt;head&gt; &lt;meta http-equiv="Content-Type" content="text/html; charset=utf-8" /&gt; &lt;title&gt;6-2.htm&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;script type="text/javascript"&gt; function createAddress(street, city, state, zip) { var obj = new Object(); obj.street = street; obj.city = city; obj.state = state; obj.zip = zip; obj.showLabel = function() { //alert(this.street + "\n" + this.city + ", " + this.state + " " + this.zip); //var obj; alert(obj.street + "\n" + obj.city + ", " + obj.state + " " + obj.zip); }; return obj; }; var JohnAddr = createAddress("12 A St.", "Johnson City", "TN", 37614); var JoeAddr = createAddress("10061 Bristol Park", "Pensacola", "FL", 32503); JohnAddr.showLabel(); JoeAddr.showLabel(); &lt;/script&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>the first commented line seems proper to me (using the <code>this</code> keyword in the showLabel function). i'm not sure how using obj in its place is working. obj would have to reference a global variable somewhere because within that function when its run there is no obj defined, right? since i make 2 objects, its not just luck in this case that both get displayed fine, the older values for obj's contents are stored and referenced properly. but how? if i uncomment the second comment then it breaks and i understand why, now im explicitly telling js that i'm talking about a local variable and there is none.</p>
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