Greasemonkey

05/20/2008 UPDATE: Check out the new version of this which is bigger, faster, stronger, and easier to configure.

So I know Greasemonkey is like a billion years old, but I finally found a use for it today and wrote my first GM script.

There was a vote today on Hacker News to ban submissions from Valleywag, mainly because they are all linkbait. For some time I have been avoiding links on HN to certain sites because my experience with them in the past has been less than great. So why not save myself the time of actually avoiding those sites and just hide them to begin with?

I put the script up on userscripts.org as HN Blacklist. Here is the source:

// ==UserScript==
// @name          HN Blacklist
// @namespace     http://news.ycombinator.com
// @description   Removes blacklisted links from Hacker News
// @include       http://news.ycombinator.com/*
// ==/UserScript==

// Written by Xichekolas ... do whatever you want with it.
// http://news.ycombinator.com/user?id=Xichekolas

// Edit this list of blacklist terms.
var blacklist = new Array('valleywag.com', 'nytimes.com');

// Just assume the stuff below will work.
var xpathnodes = document.evaluate("//a", document, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);

for(var n = 0; n < xpathnodes.snapshotLength; n++) {
  var thisnode = xpathnodes.snapshotItem(n);
  for (var i = 0; i < blacklist.length; i++) {
    if (thisnode.href.toLowerCase().indexOf(blacklist[i].toLowerCase()) > -1) {
      var grandpa = thisnode.parentNode.parentNode;
      grandpa.style['display'] = 'none';
      grandpa.nextSibling.style['display'] = 'none';
      grandpa.nextSibling.nextSibling.style['display'] = 'none';
    }
  }
}

I started out using jQuery to do this, but converting it to pure javascript was a fun experience and a worthwhile effort in itself, even if nobody actually uses this thing but me.