dd.js

getNodesHavingClassName: function(nodes, className) {
        var i,
            tagIndex,
            resultNodes = [],
            classList = [];
        for (i = 0; i < nodes.length; i += 1) {
            classList = nodes[i].className;
            classList = classList.length === 0 ? [] : classList.split(' ');
            if (!Array.prototype.indexOf) {
                tagIndex = arrayutil.indexOf(classList, className);
            } else {
                tagIndex = classList.indexOf(className);
            }
            if (tagIndex !== -1) {
                resultNodes.push(nodes[i]);
            }
        }
        
        return resultNodes;
    },
    getNodesHavingId: function(nodes, id) {
        return id;
    },
    getNodesHavingTagName: function(nodes, tagName) {
        return tagName;
    },