somewhere to talk about random ideas and projects like everyone else


November 2009 Archive

Wave uses Closure 08 November 2009

Closure Tools were recently released by Google to allow for others to use the same rich libraries that Google uses internally. Its used by Gmail, Google Docs and Google Maps, but interestingly also used by Google Wave. While they don’t actually announce that Closure is used in Wave, the view-source obfuscated mess from Wave does strongly show it.The reason why its use in wave is more interesting than most others is that Wave is in GWT, while the rest are pure JS. This implies that an interface to the Closure Library may be coming to GWT. While the interface doesn’t seem to be made from Closure, there are references to “closure_hashCode” and “”.

Wave Search Pause Button 06 November 2009

An issue now with the floods (is there any post about wave complete without a pun?) of people in wave, the with:public channel (of waves!) is becoming a unusable tsunami (har har har) of waves where clicking on one will end up opening up something else totally randomly as it has shifted down several by the time you click it.

So what is there to stop it? Well, I made this insanely great, floodwall: the Wave Pause button. It’s a simple bookmarklet that if you click, it stops all incoming updates to the search panel and clicking it again restores it.

The functional bookmarklet can be found at which is a rather hideous looking page hacked together quickly.

How does that work? Well, it turns out it’s actually not that easy. My first idea was to just find the function which updated things (it turned out to be Vwh) and replace it with function(){} and restore it later. That worked fine… But I remembered some evil crap that google said, about GWT source being browser-targeted. Incidentally that means Wave gets dfferent versions of the code with different function names, and if they ever update wave, all the function names screw up too!

Oh noes! What now? Well, it uses a sort of pseudo-heuristic approach. It searches for a big characteristic which is .style[w2g]. BUUT, w2g is fwg in chrome! So first it iterates through all variables and finds one whose value equals “display”. Then it takes that variable name, and searches for functions which have .style[name of string which equals display] twice. That reduces the pool significantly. Then it checks to make sure it has the string .innerHTML in it, and has 4 arguments. After that, well, you are reduced to a single function and you can use the same method described above.

XPath Bookmark Bookmarklet 01 November 2009

  //inspired by
  var s = document.createElement('script');
  if(typeof jQuery=='undefined') document.getElementsByTagName('head')[0].appendChild(s);
  (function() {
    if(typeof jQuery=='undefined') setTimeout(arguments.callee, 100)
        for(var path = '', elt = jQuery(this)[0]; elt && elt.nodeType==1; elt=elt.parentNode){
          var idx = jQuery(elt.parentNode).children(elt.tagName).index(elt)+1;
          idx>1 ? (idx='['+idx+']') : (idx='');
        window.location.hash = "#xpath:"+path

Sometimes you want to link to a certain part of a web page. That’s great and works well if its a nice site that clearly defines anchor tags to link to, but what if there isn’t?

Today I just remembered something and I thought that I saw something earlier with a xpath URL hash. I googled it and couldn’t find anything native to the browser (please correct me if I’m wrong) but found this script: which is basically what I was thinking about. But it was allegedly hard to make those URLs, so I thought why not make a bookmarklet to make linking to those URLs simple? So I quickly hacked this together

javascript:(function(){var a=document.createElement("script");a.setAttribute("src","");if(typeof jQuery=="undefined"){document.getElementsByTagName("head")[0].appendChild(a)}(function(){if(typeof jQuery=="undefined"){setTimeout(arguments.callee,100)}else{jQuery("*").one("click",function(d){jQuery(this)[0].scrollIntoView();for(var e="",c=jQuery(this)[0];c&&c.nodeType==1;c=c.parentNode){var b=jQuery(c.parentNode).children(c.tagName).index(c)+1;b>1?(b="["+b+"]"):(b="");e="/"+c.tagName.toLowerCase()+b+e}window.location.hash="#xpath:"+e;d.preventDefault();d.stopPropagation();jQuery("*").unbind("click",arguments.callee)})}})()})();

(Just drag it over to your bookmarks bar as with any other bookmarklet). To use, just click on the bookmark, and click on the element you want to link to. You should see the URL will update with a xpath hash showing you the copy-pastable link to that element. The code is quite simple and should work on Firefox, Chrome and all the other browsers (maybe even IE) but the ability to auto-scroll and actually use the links is only available to Firefox and potentially Opera and Chrome.

And I’m working on a Chrome Extension for the original userscript (which should work with Chrome’s userscript support, but I’m going to try packaging it as a chrome extension file) But sadly chromium for linux isnt up to speed especially with extension development.

The source can be found

Update: _Fixed the link for the path and added some stuff. Update 2_: Fixed bookmarklet, now scrolls to clicked, executes only once, prevents default