Simple DOM manipulation library. Build in progress...

dom.js

;(function(window, undefined) {
    'use strict';

    var global          = window;
    var doc             = global.document;
    var regXContainsTag = /^\s*<(\w+|!)[^>]*>/;

    var dom = function(params, context) {
        return new GetOrCreateDom(params, context);
    };

    var GetOrCreateDom = function(params, context) {
        var currentContext = doc;
        if (context) {
            currentContext = (context.nodeType) ? context : doc.querySelector(context);
        }

        if (!params || params === '' || typeof params == 'string' && params.trim() == '') {
            this.length = 0;
            return this;
        }

        if (typeof params == 'string' && regXContainsTag.test(params)) {
            // HTML string, construct domFragment, fill object and return
            var divElem = currentContext.createElement('div');
            divElem.className = 'test-wrapper';
            var docFrag = currentContext.createDocumentFragment();
            docFrag.appendChild(divElem);
            var queryDiv = docFrag.querySelector('div');
            queryDiv.innerHTML = params;
            var numChildren = queryDiv.children.length;
            // loop over nodelist and fill object
            // needs to be done because a string of html can be passed with siblings
            for (var i = 0; i < numChildren; i += 1) {
                this[i] = queryDiv.children[i];
            }
            // give the object a length value
            this.length = numChildren;
            // return object
            return this; // e.g. {0:ELEMENT_NODE,1:ELEMENT_NODE,length: 2}
        }

        // if a single node reference is passed, fill object, return object
        if (typeof params == 'object' && params.nodeName) {
            this.length = 1;
            this[0] = params;
            return this;
        }

        // if it is an object but not a node, assume nodelist or array
        // else it's a string selector, so create a nodelist
        var nodes;
        if (typeof params != 'string') {
            // nodelist or array
            nodes = params;
        }
        else {
            // string
            nodes = currentContext.querySelectorAll(params.trim());
        }
        // loop over array or nodelist created above and fill object
        var nodeLength = nodes.length;
        for (var j = 0; j < nodeLength; j += 1) {
            this[j] = nodes[j];
        }
        // assign length
        this.length = nodeLength;

        return this;
   };

   global.dom = dom;
   dom.fn = GetOrCreateDom.prototype;

})(window);