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POWhy would one use the Publish/Subscribe pattern (in JS/jQuery)?
 

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  1. POWhy would one use the Publish/Subscribe pattern (in JS/jQuery)?
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    <p>So, a colleague introduced me to the publish/subscribe pattern (in JS/jQuery), but I'm having a hard time getting to grips with <em>why</em> one would use this pattern over 'normal' JavaScript/jQuery.</p> <p>For example, previously I had the following code...</p> <pre><code>$container.on('click', '.remove_order', function(event) { event.preventDefault(); var orders = $(this).parents('form:first').find('div.order'); if (orders.length &gt; 2) { orders.last().remove(); } }); </code></pre> <p>And I could see the merit of doing this instead, for example...</p> <pre><code>removeOrder = function(orders) { if (orders.length &gt; 2) { orders.last().remove(); } } $container.on('click', '.remove_order', function(event) { event.preventDefault(); removeOrder($(this).parents('form:first').find('div.order')); }); </code></pre> <p>Because it introduces the ability to re-use the <code>removeOrder</code> functionality for different events etc.</p> <p>But why would you decide to implement the publish/subscribe pattern and go to the following lengths, if it does the same thing? (FYI, I used <a href="https://gist.github.com/661855" rel="noreferrer">jQuery tiny pub/sub</a>)</p> <pre><code>removeOrder = function(e, orders) { if (orders.length &gt; 2) { orders.last().remove(); } } $.subscribe('iquery/action/remove-order', removeOrder); $container.on('click', '.remove_order', function(event) { event.preventDefault(); $.publish('iquery/action/remove-order', $(this).parents('form:first').find('div.order')); }); </code></pre> <p>I've read about the pattern for sure, but I just can't imagine why this would ever be necessary. The tutorials I've seen that explain <em>how</em> to implement this pattern only cover just as basic examples as my own.</p> <p>I imagine that the pub/sub's usefulness would make itself apparent in a more complex application, but I can't imagine one. I'm afraid that I am completely missing the point; but I'd like to know the point if there is one!</p> <p>Could you explain <strong>succinctly</strong> why and in what situations this pattern is advantageous? Is it worth using the pub/sub pattern for code snippets like my examples above?</p>
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