Pseudointellectual Appendification

If you are writing client side JavaScript you should be using MochiKit. I found myself needing to implement two select list boxes where items are moved from one to the other. I was able to implement this with some very concise JavaScript thanks to MochiKit's functional programming and DOM manipulation APIs.

    function makeOption(option) {
      return OPTION({"value": option.value}, option.text);
    }
     
    function moveOption( fromSelect, toSelect)
    {
      // add 'selected' nodes toSelect
      appendChildNodes(toSelect,
        map( makeOption,
          ifilter(itemgetter('selected'), $(fromSelect).options))
      );

      // remove the 'selected' fromSelect
      replaceChildNodes(fromSelect,
        list(ifilterfalse(itemgetter('selected'), $(fromSelect).options))
      );
    }

You can see a working example.

There are longer and more complete examples out there, but you should be able to implement all of the functionality that they provide using MochiKit.