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POJavaScript Scope Clarification
 

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  1. POJavaScript Scope Clarification
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    <p>I've been reading just about every article I can get my hands on about JavaScript scope to better understand it. I'd like to perfectly understand it by the end. I'm currently reading this article: <a href="http://www.digital-web.com/articles/scope_in_javascript/" rel="nofollow">http://www.digital-web.com/articles/scope_in_javascript/</a> and I've just finished reading the "Complications" section (a little more than halfway down) and thought it was very helpful, but not quite clear enough.</p> <p>It uses the following code and considers the <code>onclick</code> behavior of <code>the_button</code>:</p> <pre><code>function BigComputer(answer) { this.the_answer = answer; this.ask_question = function () { alert(this.the_answer); } } function addhandler() { var deep_thought = new BigComputer(42), the_button = document.getElementById('thebutton'); the_button.onclick = deep_thought.ask_question; } window.onload = addhandler; </code></pre> <p>The article states <code>... an event handler[,] runs in a different context than when it’s executed as an object method.</code> So, if I'm to understand correctly, then the call to the <code>ask_question</code> method in context of the script's object method is <code>deep_thought.ask_question</code>, making <code>this</code> <code>deep_thought</code>. But when an event in the DOM is triggered, then the call chain changes to <code>DOMelement.eventHandler.deep_thought.ask_question</code> making <code>this</code> <code>DOMelement</code>?</p>
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    1. COYou are correct in your assumption, is there any further clarification you need? [Soshnikov](http://dmitrysoshnikov.com/ecmascript/javascript-the-core/) is my favorite resource on JavaScript internals.
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    2. COThanks for your input. I think I'm on the right track still, and I'll definitely look into that resource! I've heard a lot about Soshnikov in the JS community.
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