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POReturn "True" on Empty jQuery Selector Array?
 

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    <p>I'm working on creating a more semantic way of checking for elements with jQuery. Using <code>$("#element").length &gt; 0</code> just doesn't really feel very well worded to me, so I'm making my own selector addition for use in <code>.is</code>:</p> <pre><code>if($("#element").is(":present")) { console.log("It's aliiiveeee!!"); } </code></pre> <p>That part was easy, like this:</p> <pre><code>$.extend($.expr[':'],{ present: function(a) { return $(a).length &gt; 0; } }); </code></pre> <p>I want to go a step further, and make it easy to see if an element doesn't exist, using similar syntax:</p> <pre><code>$.extend($.expr[':'],{ present: function(a) { return $(a).length &gt; 0; }, absent: function(a) { return $(a).length === 0; } }); $(function() { if($("#element").is(":absent")) { console.log("He's dead, Jim."); } }); </code></pre> <p>But this part is surprisingly hard to do. I think it's because I'm paring down the returned elements to get a result, and paring the selector to .length === 0 is the same as asking for no elelements: it returns false no matter what.</p> <p>I've tried a lot of different ways to reverse things and get this to return true when the element doesn't exist, and false if it does:</p> <pre><code>return $(a).length === 0; return !($(a).length &gt; 0); if(!($(a).length &gt; 0)) { return true; } if($(a).length &gt; 0) { return false; } else { return true; } return !!($(a).length === 0); // etc... </code></pre> <p><strong>Is there an easy way to get this to just return true if the element doesn't exist, and false if it does?</strong></p>
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