The source code

    /*
     * This is code is also distributed under MIT license for use
     * with jQuery and prototype JavaScript libraries.
     */
    /**
     * @class Ext.DomQuery
    Provides high performance selector/xpath processing by compiling queries into reusable functions. New pseudo classes and matchers can be plugged. It works on HTML and XML documents (if a content node is passed in).
    <p>
    DomQuery supports most of the <a href="http://www.w3.org/TR/2005/WD-css3-selectors-20051215/#selectors">CSS3 selectors spec</a>, along with some custom selectors and basic XPath.</p>

    <p>
    All selectors, attribute filters and pseudos below can be combined infinitely in any order. For example "div.foo:nth-child(odd)[@foo=bar].bar:first" would be a perfectly valid selector. Node filters are processed in the order in which they appear, which allows you to optimize your queries for your document structure.
    </p>
    <h4>Element Selectors:</h4>
    <ul class="list">
        <li> <b>*</b> any element</li>
        <li> <b>E</b> an element with the tag E</li>
        <li> <b>E F</b> All descendent elements of E that have the tag F</li>
        <li> <b>E > F</b> or <b>E/F</b> all direct children elements of E that have the tag F</li>
        <li> <b>E + F</b> all elements with the tag F that are immediately preceded by an element with the tag E</li>
        <li> <b>E ~ F</b> all elements with the tag F that are preceded by a sibling element with the tag E</li>
    </ul>
    <h4>Attribute Selectors:</h4>
    <p>The use of &#64; and quotes are optional. For example, div[&#64;foo='bar'] is also a valid attribute selector.</p>
    <ul class="list">
        <li> <b>E[foo]</b> has an attribute "foo"</li>
        <li> <b>E[foo=bar]</b> has an attribute "foo" that equals "bar"</li>
        <li> <b>E[foo^=bar]</b> has an attribute "foo" that starts with "bar"</li>
        <li> <b>E[foo$=bar]</b> has an attribute "foo" that ends with "bar"</li>
        <li> <b>E[foo*=bar]</b> has an attribute "foo" that contains the substring "bar"</li>
        <li> <b>E[foo%=2]</b> has an attribute "foo" that is evenly divisible by 2</li>
        <li> <b>E[foo!=bar]</b> attribute "foo" does not equal "bar"</li>
    </ul>
    <h4>Pseudo Classes:</h4>
    <ul class="list">
        <li> <b>E:first-child</b> E is the first child of its parent</li>
        <li> <b>E:last-child</b> E is the last child of its parent</li>
        <li> <b>E:nth-child(<i>n</i>)</b> E is the <i>n</i>th child of its parent (1 based as per the spec)</li>
        <li> <b>E:nth-child(odd)</b> E is an odd child of its parent</li>
        <li> <b>E:nth-child(even)</b> E is an even child of its parent</li>
        <li> <b>E:only-child</b> E is the only child of its parent</li>
        <li> <b>E:checked</b> E is an element that is has a checked attribute that is true (e.g. a radio or checkbox) </li>
        <li> <b>E:first</b> the first E in the resultset</li>
        <li> <b>E:last</b> the last E in the resultset</li>
        <li> <b>E:nth(<i>n</i>)</b> the <i>n</i>th E in the resultset (1 based)</li>
        <li> <b>E:odd</b> shortcut for :nth-child(odd)</li>
        <li> <b>E:even</b> shortcut for :nth-child(even)</li>
        <li> <b>E:contains(foo)</b> E's innerHTML contains the substring "foo"</li>
        <li> <b>E:nodeValue(foo)</b> E contains a textNode with a nodeValue that equals "foo"</li>
        <li> <b>E:not(S)</b> an E element that does not match simple selector S</li>
        <li> <b>E:has(S)</b> an E element that has a descendent that matches simple selector S</li>
        <li> <b>E:next(S)</b> an E element whose next sibling matches simple selector S</li>
        <li> <b>E:prev(S)</b> an E element whose previous sibling matches simple selector S</li>
        <li> <b>E:any(S1|S2|S2)</b> an E element which matches any of the simple selectors S1, S2 or S3//\\</li>
    </ul>
    <h4>CSS Value Selectors:</h4>
    <ul class="list">
        <li> <b>E{display=none}</b> css value "display" that equals "none"</li>
        <li> <b>E{display^=none}</b> css value "display" that starts with "none"</li>
        <li> <b>E{display$=none}</b> css value "display" that ends with "none"</li>
        <li> <b>E{display*=none}</b> css value "display" that contains the substring "none"</li>
        <li> <b>E{display%=2}</b> css value "display" that is evenly divisible by 2</li>
        <li> <b>E{display!=none}</b> css value "display" that does not equal "none"</li>
    </ul>
     * @singleton
     */
    Ext.DomQuery = function(){
        var cache = {},
        	simpleCache = {},
        	valueCache = {},
        	nonSpace = /\S/,
        	trimRe = /^\s+|\s+$/g,
        	tplRe = /\{(\d+)\}/g,
        	modeRe = /^(\s?[\/>+~]\s?|\s|$)/,
        	tagTokenRe = /^(#)?([\w\-\*]+)/,
        	nthRe = /(\d*)n\+?(\d*)/,
        	nthRe2 = /\D/,
        	// This is for IE MSXML which does not support expandos.
    	// IE runs the same speed using setAttribute, however FF slows way down
    	// and Safari completely fails so they need to continue to use expandos.
    	isIE = window.ActiveXObject ? true : false,
    	key = 30803;

        // this eval is stop the compressor from
        // renaming the variable to something shorter
        eval("var batch = 30803;");

        // Retrieve the child node from a particular
        // parent at the specified index.
        function child(parent, index){
            var i = 0,
                n = parent.firstChild;
            while(n){
                if(n.nodeType == 1){
                   if(++i == index){
                       return n;
                   }
                }
                n = n.nextSibling;
            }
            return null;
        }

        // retrieve the next element node
        function next(n){
            while((n = n.nextSibling) && n.nodeType != 1);
            return n;
        }

        // retrieve the previous element node
        function prev(n){
            while((n = n.previousSibling) && n.nodeType != 1);
            return n;
        }

        // Mark each child node with a nodeIndex skipping and
        // removing empty text nodes.
        function children(parent){
            var n = parent.firstChild,
    	    nodeIndex = -1,
    	    nextNode;
    	while(n){
    	    nextNode = n.nextSibling;
    	    // clean worthless empty nodes.
    	    if(n.nodeType == 3 && !nonSpace.test(n.nodeValue)){
    		parent.removeChild(n);
    	    }else{
    		// add an expando nodeIndex
    		n.nodeIndex = ++nodeIndex;
    	    }
    	    n = nextNode;
    	}
    	return this;
        }

        // nodeSet - array of nodes
        // cls - CSS Class
        function byClassName(nodeSet, cls){
            if(!cls){
                return nodeSet;
            }
            var result = [], ri = -1;
            for(var i = 0, ci; ci = nodeSet[i]; i++){
                if((' '+ci.className+' ').indexOf(cls) != -1){
                    result[++ri] = ci;
                }
            }
            return result;
        };

        function attrValue(n, attr){
    	// if its an array, use the first node.
            if(!n.tagName && typeof n.length != "undefined"){
                n = n[0];
            }
            if(!n){
                return null;
            }

            if(attr == "for"){
                return n.htmlFor;
            }
            if(attr == "class" || attr == "className"){
                return n.className;
            }
            return n.getAttribute(attr) || n[attr];

        };

        // ns - nodes
        // mode - false, /, >, +, ~
        // tagName - defaults to "*"
        function getNodes(ns, mode, tagName){
            var result = [], ri = -1, cs;
            if(!ns){
                return result;
            }
            tagName = tagName || "*";
    	// convert to array
            if(typeof ns.getElementsByTagName != "undefined"){
                ns = [ns];
            }

    	// no mode specified, grab all elements by tagName
    	// at any depth
            if(!mode){
                for(var i = 0, ni; ni = ns[i]; i++){
                    cs = ni.getElementsByTagName(tagName);
                    for(var j = 0, ci; ci = cs[j]; j++){
                        result[++ri] = ci;
                    }
                }
    	// Direct Child mode (/ or >)
    	// E > F or E/F all direct children elements of E that have the tag
            } else if(mode == "/" || mode == ">"){
                var utag = tagName.toUpperCase();
                for(var i = 0, ni, cn; ni = ns[i]; i++){
                    cn = ni.childNodes;
                    for(var j = 0, cj; cj = cn[j]; j++){
                        if(cj.nodeName == utag || cj.nodeName == tagName  || tagName == '*'){
                            result[++ri] = cj;
                        }
                    }
                }
    	// Immediately Preceding mode (+)
    	// E + F all elements with the tag F that are immediately preceded by an element with the tag E
            }else if(mode == "+"){
                var utag = tagName.toUpperCase();
                for(var i = 0, n; n = ns[i]; i++){
                    while((n = n.nextSibling) && n.nodeType != 1);
                    if(n && (n.nodeName == utag || n.nodeName == tagName || tagName == '*')){
                        result[++ri] = n;
                    }
                }
    	// Sibling mode (~)
    	// E ~ F all elements with the tag F that are preceded by a sibling element with the tag E
            }else if(mode == "~"){
                var utag = tagName.toUpperCase();
                for(var i = 0, n; n = ns[i]; i++){
                    while((n = n.nextSibling)){
                        if (n.nodeName == utag || n.nodeName == tagName || tagName == '*'){
                            result[++ri] = n;
                        }
                    }
                }
            }
            return result;
        }

        function concat(a, b){
            if(b.slice){
                return a.concat(b);
            }
            for(var i = 0, l = b.length; i < l; i++){
                a[a.length] = b[i];
            }
            return a;
        }

        function byTag(cs, tagName){
            if(cs.tagName || cs == document){
                cs = [cs];
            }
            if(!tagName){
                return cs;
            }
            var result = [], ri = -1;
            tagName = tagName.toLowerCase();
            for(var i = 0, ci; ci = cs[i]; i++){
                if(ci.nodeType == 1 && ci.tagName.toLowerCase() == tagName){
                    result[++ri] = ci;
                }
            }
            return result;
        }

        function byId(cs, id){
            if(cs.tagName || cs == document){
                cs = [cs];
            }
            if(!id){
                return cs;
            }
            var result = [], ri = -1;
            for(var i = 0, ci; ci = cs[i]; i++){
                if(ci && ci.id == id){
                    result[++ri] = ci;
                    return result;
                }
            }
            return result;
        }

        // operators are =, !=, ^=, $=, *=, %=, |= and ~=
        // custom can be "{"
        function byAttribute(cs, attr, value, op, custom){
            var result = [],
                ri = -1,
                useGetStyle = custom == "{",
                fn = Ext.DomQuery.operators[op],
                a,
                xml,
                hasXml;

            for(var i = 0, ci; ci = cs[i]; i++){
    	    // skip non-element nodes.
                if(ci.nodeType != 1){
                    continue;
                }
                // only need to do this for the first node
                if(!hasXml){
                    xml = Ext.DomQuery.isXml(ci);
                    hasXml = true;
                }

                // we only need to change the property names if we're dealing with html nodes, not XML
                if(!xml){
                    if(useGetStyle){
                        a = Ext.DomQuery.getStyle(ci, attr);
                    } else if (attr == "class" || attr == "className"){
                        a = ci.className;
                    } else if (attr == "for"){
                        a = ci.htmlFor;
                    } else if (attr == "href"){
    		    // getAttribute href bug
    		    // http://www.glennjones.net/Post/809/getAttributehrefbug.htm
                        a = ci.getAttribute("href", 2);
                    } else{
                        a = ci.getAttribute(attr);
                    }
                }else{
                    a = ci.getAttribute(attr);
                }
                if((fn && fn(a, value)) || (!fn && a)){
                    result[++ri] = ci;
                }
            }
            return result;
        }

        function byPseudo(cs, name, value){
            return Ext.DomQuery.pseudos[name](cs, value);
        }

        function nodupIEXml(cs){
            var d = ++key,
                r;
            cs[0].setAttribute("_nodup", d);
            r = [cs[0]];
            for(var i = 1, len = cs.length; i < len; i++){
                var c = cs[i];
                if(!c.getAttribute("_nodup") != d){
                    c.setAttribute("_nodup", d);
                    r[r.length] = c;
                }
            }
            for(var i = 0, len = cs.length; i < len; i++){
                cs[i].removeAttribute("_nodup");
            }
            return r;
        }

        function nodup(cs){
            if(!cs){
                return [];
            }
            var len = cs.length, c, i, r = cs, cj, ri = -1;
            if(!len || typeof cs.nodeType != "undefined" || len == 1){
                return cs;
            }
            if(isIE && typeof cs[0].selectSingleNode != "undefined"){
                return nodupIEXml(cs);
            }
            var d = ++key;
            cs[0]._nodup = d;
            for(i = 1; c = cs[i]; i++){
                if(c._nodup != d){
                    c._nodup = d;
                }else{
                    r = [];
                    for(var j = 0; j < i; j++){
                        r[++ri] = cs[j];
                    }
                    for(j = i+1; cj = cs[j]; j++){
                        if(cj._nodup != d){
                            cj._nodup = d;
                            r[++ri] = cj;
                        }
                    }
                    return r;
                }
            }
            return r;
        }

        function quickDiffIEXml(c1, c2){
            var d = ++key,
                r = [];
            for(var i = 0, len = c1.length; i < len; i++){
                c1[i].setAttribute("_qdiff", d);
            }
            for(var i = 0, len = c2.length; i < len; i++){
                if(c2[i].getAttribute("_qdiff") != d){
                    r[r.length] = c2[i];
                }
            }
            for(var i = 0, len = c1.length; i < len; i++){
               c1[i].removeAttribute("_qdiff");
            }
            return r;
        }

        function quickDiff(c1, c2){
            var len1 = c1.length,
            	d = ++key,
            	r = [];
            if(!len1){
                return c2;
            }
            if(isIE && typeof c1[0].selectSingleNode != "undefined"){
                return quickDiffIEXml(c1, c2);
            }
            for(var i = 0; i < len1; i++){
                c1[i]._qdiff = d;
            }
            for(var i = 0, len = c2.length; i < len; i++){
                if(c2[i]._qdiff != d){
                    r[r.length] = c2[i];
                }
            }
            return r;
        }

        function quickId(ns, mode, root, id){
            if(ns == root){
               var d = root.ownerDocument || root;
               return d.getElementById(id);
            }
            ns = getNodes(ns, mode, "*");
            return byId(ns, id);
        }

        return {
            getStyle : function(el, name){
                return Ext.fly(el).getStyle(name);
            },
            /**
             * Compiles a selector/xpath query into a reusable function. The returned function
             * takes one parameter "root" (optional), which is the context node from where the query should start.
             * @param {String} selector The selector/xpath query
             * @param {String} type (optional) Either "select" (the default) or "simple" for a simple selector match
             * @return {Function}
             */
            compile : function(path, type){
                type = type || "select";

        	    // setup fn preamble
                var fn = ["var f = function(root){\n var mode; ++batch; var n = root || document;\n"],
            		mode,
            		lastPath,
                	matchers = Ext.DomQuery.matchers,
                	matchersLn = matchers.length,
                	modeMatch,
                	// accept leading mode switch
                	lmode = path.match(modeRe);

                if(lmode && lmode[1]){
                    fn[fn.length] = 'mode="'+lmode[1].replace(trimRe, "")+'";';
                    path = path.replace(lmode[1], "");
                }

                // strip leading slashes
                while(path.substr(0, 1)=="/"){
                    path = path.substr(1);
                }

                while(path && lastPath != path){
                    lastPath = path;
                    var tokenMatch = path.match(tagTokenRe);
                    if(type == "select"){
                        if(tokenMatch){
    			// ID Selector
                            if(tokenMatch[1] == "#"){
                                fn[fn.length] = 'n = quickId(n, mode, root, "'+tokenMatch[2]+'");';
                            }else{
                                fn[fn.length] = 'n = getNodes(n, mode, "'+tokenMatch[2]+'");';
                            }
                            path = path.replace(tokenMatch[0], "");
                        }else if(path.substr(0, 1) != '@'){
                            fn[fn.length] = 'n = getNodes(n, mode, "*");';
                        }
    		// type of "simple"
                    }else{
                        if(tokenMatch){
                            if(tokenMatch[1] == "#"){
                                fn[fn.length] = 'n = byId(n, "'+tokenMatch[2]+'");';
                            }else{
                                fn[fn.length] = 'n = byTag(n, "'+tokenMatch[2]+'");';
                            }
                            path = path.replace(tokenMatch[0], "");
                        }
                    }
                    while(!(modeMatch = path.match(modeRe))){
                        var matched = false;
                        for(var j = 0; j < matchersLn; j++){
                            var t = matchers[j];
                            var m = path.match(t.re);
                            if(m){
                                fn[fn.length] = t.select.replace(tplRe, function(x, i){
    				return m[i];
    			    });
                                path = path.replace(m[0], "");
                                matched = true;
                                break;
                            }
                        }
                        // prevent infinite loop on bad selector
                        if(!matched){
                            throw 'Error parsing selector, parsing failed at "' + path + '"';
                        }
                    }
                    if(modeMatch[1]){
                        fn[fn.length] = 'mode="'+modeMatch[1].replace(trimRe, "")+'";';
                        path = path.replace(modeMatch[1], "");
                    }
                }
    	    // close fn out
                fn[fn.length] = "return nodup(n);\n}";

    	    // eval fn and return it
                eval(fn.join(""));
                return f;
            },

            /**
             * Selects a group of elements.
             * @param {String} selector The selector/xpath query (can be a comma separated list of selectors)
             * @param {Node/String} root (optional) The start of the query (defaults to document).
             * @return {Array} An Array of DOM elements which match the selector. If there are
             * no matches, and empty Array is returned.
             */
    	jsSelect: function(path, root, type){
    	    // set root to doc if not specified.
    	    root = root || document;

                if(typeof root == "string"){
                    root = document.getElementById(root);
                }
                var paths = path.split(","),
                	results = [];

    	    // loop over each selector
                for(var i = 0, len = paths.length; i < len; i++){
                    var subPath = paths[i].replace(trimRe, "");
    		// compile and place in cache
                    if(!cache[subPath]){
                        cache[subPath] = Ext.DomQuery.compile(subPath);
                        if(!cache[subPath]){
                            throw subPath + " is not a valid selector";
                        }
                    }
                    var result = cache[subPath](root);
                    if(result && result != document){
                        results = results.concat(result);
                    }
                }

    	    // if there were multiple selectors, make sure dups
    	    // are eliminated
                if(paths.length > 1){
                    return nodup(results);
                }
                return results;
            },
    	isXml: function(el) {
    	    var docEl = (el ? el.ownerDocument || el : 0).documentElement;
    	    return docEl ? docEl.nodeName !== "HTML" : false;
    	},
            select : document.querySelectorAll ? function(path, root, type) {
    	    root = root || document;
    	    if (!Ext.DomQuery.isXml(root)) {
    		try {
    		    var cs = root.querySelectorAll(path);
    		    return Ext.toArray(cs);
    		}
    		catch (ex) {}
    	    }
    	    return Ext.DomQuery.jsSelect.call(this, path, root, type);
    	} : function(path, root, type) {
    	    return Ext.DomQuery.jsSelect.call(this, path, root, type);
    	},

            /**
             * Selects a single element.
             * @param {String} selector The selector/xpath query
             * @param {Node} root (optional) The start of the query (defaults to document).
             * @return {Element} The DOM element which matched the selector.
             */
            selectNode : function(path, root){
                return Ext.DomQuery.select(path, root)[0];
            },

            /**
             * Selects the value of a node, optionally replacing null with the defaultValue.
             * @param {String} selector The selector/xpath query
             * @param {Node} root (optional) The start of the query (defaults to document).
             * @param {String} defaultValue (optional)
             * @return {String}
             */
            selectValue : function(path, root, defaultValue){
                path = path.replace(trimRe, "");
                if(!valueCache[path]){
                    valueCache[path] = Ext.DomQuery.compile(path, "select");
                }
                var n = valueCache[path](root), v;
                n = n[0] ? n[0] : n;

    	    // overcome a limitation of maximum textnode size
    	    // Rumored to potentially crash IE6 but has not been confirmed.
    	    // http://reference.sitepoint.com/javascript/Node/normalize
    	    // https://developer.mozilla.org/En/DOM/Node.normalize
                if (typeof n.normalize == 'function') n.normalize();

                v = (n && n.firstChild ? n.firstChild.nodeValue : null);
                return ((v === null||v === undefined||v==='') ? defaultValue : v);
            },

            /**
             * Selects the value of a node, parsing integers and floats. Returns the defaultValue, or 0 if none is specified.
             * @param {String} selector The selector/xpath query
             * @param {Node} root (optional) The start of the query (defaults to document).
             * @param {Number} defaultValue (optional)
             * @return {Number}
             */
            selectNumber : function(path, root, defaultValue){
                var v = Ext.DomQuery.selectValue(path, root, defaultValue || 0);
                return parseFloat(v);
            },

            /**
             * Returns true if the passed element(s) match the passed simple selector (e.g. div.some-class or span:first-child)
             * @param {String/HTMLElement/Array} el An element id, element or array of elements
             * @param {String} selector The simple selector to test
             * @return {Boolean}
             */
            is : function(el, ss){
                if(typeof el == "string"){
                    el = document.getElementById(el);
                }
                var isArray = Ext.isArray(el),
                	result = Ext.DomQuery.filter(isArray ? el : [el], ss);
                return isArray ? (result.length == el.length) : (result.length > 0);
            },

            /**
             * Filters an array of elements to only include matches of a simple selector (e.g. div.some-class or span:first-child)
             * @param {Array} el An array of elements to filter
             * @param {String} selector The simple selector to test
             * @param {Boolean} nonMatches If true, it returns the elements that DON'T match
             * the selector instead of the ones that match
             * @return {Array} An Array of DOM elements which match the selector. If there are
             * no matches, and empty Array is returned.
             */
            filter : function(els, ss, nonMatches){
                ss = ss.replace(trimRe, "");
                if(!simpleCache[ss]){
                    simpleCache[ss] = Ext.DomQuery.compile(ss, "simple");
                }
                var result = simpleCache[ss](els);
                return nonMatches ? quickDiff(result, els) : result;
            },

            /**
             * Collection of matching regular expressions and code snippets.
             * Each capture group within () will be replace the {} in the select
             * statement as specified by their index.
             */
            matchers : [{
                    re: /^\.([\w\-]+)/,
                    select: 'n = byClassName(n, " {1} ");'
                }, {
                    re: /^\:([\w\-]+)(?:\(((?:[^\s>\/]*|.*?))\))?/,
                    select: 'n = byPseudo(n, "{1}", "{2}");'
                },{
                    re: /^(?:([\[\{])(?:@)?([\w\-]+)\s?(?:(=|.=)\s?(["']?)(.*?)\4)?[\]\}])/,
                    select: 'n = byAttribute(n, "{2}", "{5}", "{3}", "{1}");'
                }, {
                    re: /^#([\w\-]+)/,
                    select: 'n = byId(n, "{1}");'
                },{
                    re: /^@([\w\-]+)/,
                    select: 'return {firstChild:{nodeValue:attrValue(n, "{1}")}};'
                }
            ],

            /**
             * Collection of operator comparison functions. The default operators are =, !=, ^=, $=, *=, %=, |= and ~=.
             * New operators can be added as long as the match the format <i>c</i>= where <i>c</i> is any character other than space, &gt; &lt;.
             */
            operators : {
                "=" : function(a, v){
                    return a == v;
                },
                "!=" : function(a, v){
                    return a != v;
                },
                "^=" : function(a, v){
                    return a && a.substr(0, v.length) == v;
                },
                "$=" : function(a, v){
                    return a && a.substr(a.length-v.length) == v;
                },
                "*=" : function(a, v){
                    return a && a.indexOf(v) !== -1;
                },
                "%=" : function(a, v){
                    return (a % v) == 0;
                },
                "|=" : function(a, v){
                    return a && (a == v || a.substr(0, v.length+1) == v+'-');
                },
                "~=" : function(a, v){
                    return a && (' '+a+' ').indexOf(' '+v+' ') != -1;
                }
            },

            /**
             * <p>Object hash of "pseudo class" filter functions which are used when filtering selections. Each function is passed
             * two parameters:</p><div class="mdetail-params"><ul>
             * <li><b>c</b> : Array<div class="sub-desc">An Array of DOM elements to filter.</div></li>
             * <li><b>v</b> : String<div class="sub-desc">The argument (if any) supplied in the selector.</div></li>
             * </ul></div>
             * <p>A filter function returns an Array of DOM elements which conform to the pseudo class.</p>
             * <p>In addition to the provided pseudo classes listed above such as <code>first-child</code> and <code>nth-child</code>,
             * developers may add additional, custom psuedo class filters to select elements according to application-specific requirements.</p>
             * <p>For example, to filter <code>&lt;a></code> elements to only return links to <i>external</i> resources:</p>
             * <code><pre>
    Ext.DomQuery.pseudos.external = function(c, v){
        var r = [], ri = -1;
        for(var i = 0, ci; ci = c[i]; i++){
    //      Include in result set only if it's a link to an external resource
            if(ci.hostname != location.hostname){
                r[++ri] = ci;
            }
        }
        return r;
    };</pre></code>
             * Then external links could be gathered with the following statement:<code><pre>
    var externalLinks = Ext.select("a:external");
    </code></pre>
             */
            pseudos : {
                "first-child" : function(c){
                    var r = [], ri = -1, n;
                    for(var i = 0, ci; ci = n = c[i]; i++){
                        while((n = n.previousSibling) && n.nodeType != 1);
                        if(!n){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "last-child" : function(c){
                    var r = [], ri = -1, n;
                    for(var i = 0, ci; ci = n = c[i]; i++){
                        while((n = n.nextSibling) && n.nodeType != 1);
                        if(!n){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "nth-child" : function(c, a) {
                    var r = [], ri = -1,
                    	m = nthRe.exec(a == "even" && "2n" || a == "odd" && "2n+1" || !nthRe2.test(a) && "n+" + a || a),
                    	f = (m[1] || 1) - 0, l = m[2] - 0;
                    for(var i = 0, n; n = c[i]; i++){
                        var pn = n.parentNode;
                        if (batch != pn._batch) {
                            var j = 0;
                            for(var cn = pn.firstChild; cn; cn = cn.nextSibling){
                                if(cn.nodeType == 1){
                                   cn.nodeIndex = ++j;
                                }
                            }
                            pn._batch = batch;
                        }
                        if (f == 1) {
                            if (l == 0 || n.nodeIndex == l){
                                r[++ri] = n;
                            }
                        } else if ((n.nodeIndex + l) % f == 0){
                            r[++ri] = n;
                        }
                    }

                    return r;
                },

                "only-child" : function(c){
                    var r = [], ri = -1;;
                    for(var i = 0, ci; ci = c[i]; i++){
                        if(!prev(ci) && !next(ci)){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "empty" : function(c){
                    var r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        var cns = ci.childNodes, j = 0, cn, empty = true;
                        while(cn = cns[j]){
                            ++j;
                            if(cn.nodeType == 1 || cn.nodeType == 3){
                                empty = false;
                                break;
                            }
                        }
                        if(empty){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "contains" : function(c, v){
                    var r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        if((ci.textContent||ci.innerText||'').indexOf(v) != -1){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "nodeValue" : function(c, v){
                    var r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        if(ci.firstChild && ci.firstChild.nodeValue == v){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "checked" : function(c){
                    var r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        if(ci.checked == true){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "not" : function(c, ss){
                    return Ext.DomQuery.filter(c, ss, true);
                },

                "any" : function(c, selectors){
                    var ss = selectors.split('|'),
                    	r = [], ri = -1, s;
                    for(var i = 0, ci; ci = c[i]; i++){
                        for(var j = 0; s = ss[j]; j++){
                            if(Ext.DomQuery.is(ci, s)){
                                r[++ri] = ci;
                                break;
                            }
                        }
                    }
                    return r;
                },

                "odd" : function(c){
                    return this["nth-child"](c, "odd");
                },

                "even" : function(c){
                    return this["nth-child"](c, "even");
                },

                "nth" : function(c, a){
                    return c[a-1] || [];
                },

                "first" : function(c){
                    return c[0] || [];
                },

                "last" : function(c){
                    return c[c.length-1] || [];
                },

                "has" : function(c, ss){
                    var s = Ext.DomQuery.select,
                    	r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        if(s(ss, ci).length > 0){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "next" : function(c, ss){
                    var is = Ext.DomQuery.is,
                    	r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        var n = next(ci);
                        if(n && is(n, ss)){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                },

                "prev" : function(c, ss){
                    var is = Ext.DomQuery.is,
                    	r = [], ri = -1;
                    for(var i = 0, ci; ci = c[i]; i++){
                        var n = prev(ci);
                        if(n && is(n, ss)){
                            r[++ri] = ci;
                        }
                    }
                    return r;
                }
            }
        };
    }();

    /**
     * Selects an array of DOM nodes by CSS/XPath selector. Shorthand of {@link Ext.DomQuery#select}
     * @param {String} path The selector/xpath query
     * @param {Node} root (optional) The start of the query (defaults to document).
     * @return {Array}
     * @member Ext
     * @method query
     */
    Ext.query = Ext.DomQuery.select;