JavaScript snippet to highlight new posts

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JavaScript snippet to highlight new posts

Hi all. I wanted an easy way to highlight new posts, without basing it on the last time I visited a page. The snippet is as follows, if any of you folks would like to use it: /** * Usage: highlight('newpost', 3, 'hours'); * * This will add the class 'newpost' to any post made within * the past 3 hours. This includes, for example: * * 3 hours ago * 45 minutes ago * 22 seconds ago */ function highlight(className, number, type) { var types = ['second', 'seconds', 'minute', 'minutes', 'hour', 'hours', 'day', 'days']; // Types are inclusive, so if we filtered to 'minutes', then // we always want posts that were made 'seconds' ago. types = types.slice(0, types.indexOf(type) + 1); // Any link with 'item?id' is assumed to be a timestamp. var posts = document.querySelectorAll('a[href*="item?id"]'); // Loop through the number of posts, since we need to access // each post using NodeList#item. for(var i = 0; i < posts.length; i++) { var post = posts.item(i); try { // The leftmost integer. var label_number = parseInt(post.innerHTML.match(/^\d+/)); // The label (a value that maps up to the types array). var label_type = post.innerHTML.match(/^\d+ (.+?) ago$/)[1]; } catch(e) { // If either of the matches fail, it's due to an // irrelevant link. continue; } // Continue if the label is out of bounds. // For instance, 'days' when filtering by 'minutes'. if(types.indexOf(label_type) === -1) continue; // Continue if the label type matches, but the number // is larger than what we're filtering for. if(type === label_type && label_number > number) continue; // td > div > span > a post.parentNode.parentNode.parentNode.className += ' ' + className; } }