source: Dev/branches/rest-dojo-ui/client/dojo/query.js @ 263

define(["./_base/kernel", "./has", "./dom", "./on", "./_base/array", "./_base/lang", "./selector/_loader", "./selector/_loader!default"],
        function(dojo, has, dom, on, array, lang, loader, defaultEngine){
"use strict";

        has.add("array-extensible", function(){
                // test to see if we can extend an array (not supported in old IE)
                return lang.delegate([], {length: 1}).length == 1 && !has("bug-for-in-skips-shadowed");
        });
        
        var ap = Array.prototype, aps = ap.slice, apc = ap.concat, forEach = array.forEach;

        var tnl = function(/*Array*/ a, /*dojo.NodeList?*/ parent, /*Function?*/ NodeListCtor){
                // summary:
                //              decorate an array to make it look like a `dojo.NodeList`.
                // a:
                //              Array of nodes to decorate.
                // parent:
                //              An optional parent NodeList that generated the current
                //              list of nodes. Used to call _stash() so the parent NodeList
                //              can be accessed via end() later.
                // NodeListCtor:
                //              An optional constructor function to use for any
                //              new NodeList calls. This allows a certain chain of
                //              NodeList calls to use a different object than dojo.NodeList.
                var nodeList = new (NodeListCtor || this._NodeListCtor || nl)(a);
                return parent ? nodeList._stash(parent) : nodeList;
        };

        var loopBody = function(f, a, o){
                a = [0].concat(aps.call(a, 0));
                o = o || dojo.global;
                return function(node){
                        a[0] = node;
                        return f.apply(o, a);
                };
        };

        // adapters

        var adaptAsForEach = function(f, o){
                // summary:
                //              adapts a single node function to be used in the forEach-type
                //              actions. The initial object is returned from the specialized
                //              function.
                // f: Function
                //              a function to adapt
                // o: Object?
                //              an optional context for f
                return function(){
                        this.forEach(loopBody(f, arguments, o));
                        return this;    // Object
                };
        };

        var adaptAsMap = function(f, o){
                // summary:
                //              adapts a single node function to be used in the map-type
                //              actions. The return is a new array of values, as via `dojo.map`
                // f: Function
                //              a function to adapt
                // o: Object?
                //              an optional context for f
                return function(){
                        return this.map(loopBody(f, arguments, o));
                };
        };

        var adaptAsFilter = function(f, o){
                // summary:
                //              adapts a single node function to be used in the filter-type actions
                // f: Function
                //              a function to adapt
                // o: Object?
                //              an optional context for f
                return function(){
                        return this.filter(loopBody(f, arguments, o));
                };
        };

        var adaptWithCondition = function(f, g, o){
                // summary:
                //              adapts a single node function to be used in the map-type
                //              actions, behaves like forEach() or map() depending on arguments
                // f: Function
                //              a function to adapt
                // g: Function
                //              a condition function, if true runs as map(), otherwise runs as forEach()
                // o: Object?
                //              an optional context for f and g
                return function(){
                        var a = arguments, body = loopBody(f, a, o);
                        if(g.call(o || dojo.global, a)){
                                return this.map(body);  // self
                        }
                        this.forEach(body);
                        return this;    // self
                };
        };

        var NodeList = function(array){
                // summary:
                //              dojo.NodeList is an of Array-like object which adds syntactic
                //              sugar for chaining, common iteration operations, animation, and
                //              node manipulation. NodeLists are most often returned as the
                //              result of dojo.query() calls.
                // description:
                //              dojo.NodeList instances provide many utilities that reflect
                //              core Dojo APIs for Array iteration and manipulation, DOM
                //              manipulation, and event handling. Instead of needing to dig up
                //              functions in the dojo.* namespace, NodeLists generally make the
                //              full power of Dojo available for DOM manipulation tasks in a
                //              simple, chainable way.
                // example:
                //              create a node list from a node
                //              |       new dojo.NodeList(dojo.byId("foo"));
                // example:
                //              get a NodeList from a CSS query and iterate on it
                //              |       var l = dojo.query(".thinger");
                //              |       l.forEach(function(node, index, nodeList){
                //              |               console.log(index, node.innerHTML);
                //              |       });
                // example:
                //              use native and Dojo-provided array methods to manipulate a
                //              NodeList without needing to use dojo.* functions explicitly:
                //              |       var l = dojo.query(".thinger");
                //              |       // since NodeLists are real arrays, they have a length
                //              |       // property that is both readable and writable and
                //              |       // push/pop/shift/unshift methods
                //              |       console.log(l.length);
                //              |       l.push(dojo.create("span"));
                //              |
                //              |       // dojo's normalized array methods work too:
                //              |       console.log( l.indexOf(dojo.byId("foo")) );
                //              |       // ...including the special "function as string" shorthand
                //              |       console.log( l.every("item.nodeType == 1") );
                //              |
                //              |       // NodeLists can be [..] indexed, or you can use the at()
                //              |       // function to get specific items wrapped in a new NodeList:
                //              |       var node = l[3]; // the 4th element
                //              |       var newList = l.at(1, 3); // the 2nd and 4th elements
                // example:
                //              the style functions you expect are all there too:
                //              |       // style() as a getter...
                //              |       var borders = dojo.query(".thinger").style("border");
                //              |       // ...and as a setter:
                //              |       dojo.query(".thinger").style("border", "1px solid black");
                //              |       // class manipulation
                //              |       dojo.query("li:nth-child(even)").addClass("even");
                //              |       // even getting the coordinates of all the items
                //              |       var coords = dojo.query(".thinger").coords();
                // example:
                //              DOM manipulation functions from the dojo.* namespace area also
                //              available:
                //              |       // remove all of the elements in the list from their
                //              |       // parents (akin to "deleting" them from the document)
                //              |       dojo.query(".thinger").orphan();
                //              |       // place all elements in the list at the front of #foo
                //              |       dojo.query(".thinger").place("foo", "first");
                // example:
                //              Event handling couldn't be easier. `dojo.connect` is mapped in,
                //              and shortcut handlers are provided for most DOM events:
                //              |       // like dojo.connect(), but with implicit scope
                //              |       dojo.query("li").connect("onclick", console, "log");
                //              |
                //              |       // many common event handlers are already available directly:
                //              |       dojo.query("li").onclick(console, "log");
                //              |       var toggleHovered = dojo.hitch(dojo, "toggleClass", "hovered");
                //              |       dojo.query("p")
                //              |               .onmouseenter(toggleHovered)
                //              |               .onmouseleave(toggleHovered);
                // example:
                //              chainability is a key advantage of NodeLists:
                //              |       dojo.query(".thinger")
                //              |               .onclick(function(e){ /* ... */ })
                //              |               .at(1, 3, 8) // get a subset
                //              |                       .style("padding", "5px")
                //              |                       .forEach(console.log);
                var isNew = this instanceof nl && has("array-extensible");
                if(typeof array == "number"){
                        array = Array(array);
                }
                var nodeArray = (array && "length" in array) ? array : arguments;
                if(isNew || !nodeArray.sort){
                        // make sure it's a real array before we pass it on to be wrapped 
                        var target = isNew ? this : [],
                                l = target.length = nodeArray.length;
                        for(var i = 0; i < l; i++){
                                target[i] = nodeArray[i];
                        }
                        if(isNew){
                                // called with new operator, this means we are going to use this instance and push
                                // the nodes on to it. This is usually much faster since the NodeList properties
                                //      don't need to be copied (unless the list of nodes is extremely large).
                                return target;
                        }
                        nodeArray = target;
                }
                // called without new operator, use a real array and copy prototype properties,
                // this is slower and exists for back-compat. Should be removed in 2.0.
                lang._mixin(nodeArray, nlp);
                nodeArray._NodeListCtor = function(array){
                        // call without new operator to preserve back-compat behavior
                        return nl(array);
                };
                return nodeArray;
        };
        
        var nl = NodeList, nlp = nl.prototype = 
                has("array-extensible") ? [] : {};// extend an array if it is extensible

        // expose adapters and the wrapper as private functions

        nl._wrap = nlp._wrap = tnl;
        nl._adaptAsMap = adaptAsMap;
        nl._adaptAsForEach = adaptAsForEach;
        nl._adaptAsFilter  = adaptAsFilter;
        nl._adaptWithCondition = adaptWithCondition;

        // mass assignment

        // add array redirectors
        forEach(["slice", "splice"], function(name){
                var f = ap[name];
                //Use a copy of the this array via this.slice() to allow .end() to work right in the splice case.
                // CANNOT apply ._stash()/end() to splice since it currently modifies
                // the existing this array -- it would break backward compatibility if we copy the array before
                // the splice so that we can use .end(). So only doing the stash option to this._wrap for slice.
                nlp[name] = function(){ return this._wrap(f.apply(this, arguments), name == "slice" ? this : null); };
        });
        // concat should be here but some browsers with native NodeList have problems with it

        // add array.js redirectors
        forEach(["indexOf", "lastIndexOf", "every", "some"], function(name){
                var f = array[name];
                nlp[name] = function(){ return f.apply(dojo, [this].concat(aps.call(arguments, 0))); };
        });

        /*===== var NodeList = dojo.NodeList; =====*/
        lang.extend(NodeList, {
                // copy the constructors
                constructor: nl,
                _NodeListCtor: nl,
                toString: function(){
                        // Array.prototype.toString can't be applied to objects, so we use join
                        return this.join(",");
                },
                _stash: function(parent){
                        // summary:
                        //              private function to hold to a parent NodeList. end() to return the parent NodeList.
                        //
                        // example:
                        // How to make a `dojo.NodeList` method that only returns the third node in
                        // the dojo.NodeList but allows access to the original NodeList by using this._stash:
                        //      |       dojo.extend(dojo.NodeList, {
                        //      |               third: function(){
                        //      |                       var newNodeList = dojo.NodeList(this[2]);
                        //      |                       return newNodeList._stash(this);
                        //      |               }
                        //      |       });
                        //      |       // then see how _stash applies a sub-list, to be .end()'ed out of
                        //      |       dojo.query(".foo")
                        //      |               .third()
                        //      |                       .addClass("thirdFoo")
                        //      |               .end()
                        //      |               // access to the orig .foo list
                        //      |               .removeClass("foo")
                        //      |
                        //
                        this._parent = parent;
                        return this; //dojo.NodeList
                },

                on: function(eventName, listener){
                        // summary:
                        //              Listen for events on the nodes in the NodeList. Basic usage is:
                        //              | query(".my-class").on("click", listener);
                        //              This supports event delegation by using selectors as the first argument with the event names as
                        //              pseudo selectors. For example:
                        //              | dojo.query("#my-list").on("li:click", listener);
                        //              This will listen for click events within <li> elements that are inside the #my-list element.
                        //              Because on supports CSS selector syntax, we can use comma-delimited events as well:
                        //              | dojo.query("#my-list").on("li button:mouseover, li:click", listener);
                        var handles = this.map(function(node){
                                return on(node, eventName, listener); // TODO: apply to the NodeList so the same selector engine is used for matches
                        });
                        handles.remove = function(){
                                for(var i = 0; i < handles.length; i++){
                                        handles[i].remove();
                                }
                        };
                        return handles;
                },

                end: function(){
                        // summary:
                        //              Ends use of the current `dojo.NodeList` by returning the previous dojo.NodeList
                        //              that generated the current dojo.NodeList.
                        // description:
                        //              Returns the `dojo.NodeList` that generated the current `dojo.NodeList`. If there
                        //              is no parent dojo.NodeList, an empty dojo.NodeList is returned.
                        // example:
                        //      |       dojo.query("a")
                        //      |               .filter(".disabled")
                        //      |                       // operate on the anchors that only have a disabled class
                        //      |                       .style("color", "grey")
                        //      |               .end()
                        //      |               // jump back to the list of anchors
                        //      |               .style(...)
                        //
                        if(this._parent){
                                return this._parent;
                        }else{
                                //Just return empty list.
                                return new this._NodeListCtor(0);
                        }
                },

                // http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array#Methods

                // FIXME: handle return values for #3244
                //              http://trac.dojotoolkit.org/ticket/3244

                // FIXME:
                //              need to wrap or implement:
                //                      join (perhaps w/ innerHTML/outerHTML overload for toString() of items?)
                //                      reduce
                //                      reduceRight

                /*=====
                slice: function(begin, end){
                        // summary:
                        //              Returns a new NodeList, maintaining this one in place
                        // description:
                        //              This method behaves exactly like the Array.slice method
                        //              with the caveat that it returns a dojo.NodeList and not a
                        //              raw Array. For more details, see Mozilla's (slice
                        //              documentation)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:slice]
                        // begin: Integer
                        //              Can be a positive or negative integer, with positive
                        //              integers noting the offset to begin at, and negative
                        //              integers denoting an offset from the end (i.e., to the left
                        //              of the end)
                        // end: Integer?
                        //              Optional parameter to describe what position relative to
                        //              the NodeList's zero index to end the slice at. Like begin,
                        //              can be positive or negative.
                        return this._wrap(a.slice.apply(this, arguments));
                },

                splice: function(index, howmany, item){
                        // summary:
                        //              Returns a new NodeList, manipulating this NodeList based on
                        //              the arguments passed, potentially splicing in new elements
                        //              at an offset, optionally deleting elements
                        // description:
                        //              This method behaves exactly like the Array.splice method
                        //              with the caveat that it returns a dojo.NodeList and not a
                        //              raw Array. For more details, see Mozilla's (splice
                        //              documentation)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:splice]
                        //              For backwards compatibility, calling .end() on the spliced NodeList
                        //              does not return the original NodeList -- splice alters the NodeList in place.
                        // index: Integer
                        //              begin can be a positive or negative integer, with positive
                        //              integers noting the offset to begin at, and negative
                        //              integers denoting an offset from the end (i.e., to the left
                        //              of the end)
                        // howmany: Integer?
                        //              Optional parameter to describe what position relative to
                        //              the NodeList's zero index to end the slice at. Like begin,
                        //              can be positive or negative.
                        // item: Object...?
                        //              Any number of optional parameters may be passed in to be
                        //              spliced into the NodeList
                        // returns:
                        //              dojo.NodeList
                        return this._wrap(a.splice.apply(this, arguments));
                },

                indexOf: function(value, fromIndex){
                        // summary:
                        //              see dojo.indexOf(). The primary difference is that the acted-on
                        //              array is implicitly this NodeList
                        // value: Object:
                        //              The value to search for.
                        // fromIndex: Integer?:
                        //              The location to start searching from. Optional. Defaults to 0.
                        // description:
                        //              For more details on the behavior of indexOf, see Mozilla's
                        //              (indexOf
                        //              docs)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:indexOf]
                        // returns:
                        //              Positive Integer or 0 for a match, -1 of not found.
                        return d.indexOf(this, value, fromIndex); // Integer
                },

                lastIndexOf: function(value, fromIndex){
                        // summary:
                        //              see dojo.lastIndexOf(). The primary difference is that the
                        //              acted-on array is implicitly this NodeList
                        // description:
                        //              For more details on the behavior of lastIndexOf, see
                        //              Mozilla's (lastIndexOf
                        //              docs)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:lastIndexOf]
                        // value: Object
                        //              The value to search for.
                        // fromIndex: Integer?
                        //              The location to start searching from. Optional. Defaults to 0.
                        // returns:
                        //              Positive Integer or 0 for a match, -1 of not found.
                        return d.lastIndexOf(this, value, fromIndex); // Integer
                },

                every: function(callback, thisObject){
                        // summary:
                        //              see `dojo.every()` and the (Array.every
                        //              docs)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:every].
                        //              Takes the same structure of arguments and returns as
                        //              dojo.every() with the caveat that the passed array is
                        //              implicitly this NodeList
                        // callback: Function: the callback
                        // thisObject: Object?: the context
                        return d.every(this, callback, thisObject); // Boolean
                },

                some: function(callback, thisObject){
                        // summary:
                        //              Takes the same structure of arguments and returns as
                        //              `dojo.some()` with the caveat that the passed array is
                        //              implicitly this NodeList.  See `dojo.some()` and Mozilla's
                        //              (Array.some
                        //              documentation)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:some].
                        // callback: Function: the callback
                        // thisObject: Object?: the context
                        return d.some(this, callback, thisObject); // Boolean
                },
                =====*/

                concat: function(item){
                        // summary:
                        //              Returns a new NodeList comprised of items in this NodeList
                        //              as well as items passed in as parameters
                        // description:
                        //              This method behaves exactly like the Array.concat method
                        //              with the caveat that it returns a `dojo.NodeList` and not a
                        //              raw Array. For more details, see the (Array.concat
                        //              docs)[http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Global_Objects:Array:concat]
                        // item: Object?
                        //              Any number of optional parameters may be passed in to be
                        //              spliced into the NodeList
                        // returns:
                        //              dojo.NodeList

                        //return this._wrap(apc.apply(this, arguments));
                        // the line above won't work for the native NodeList :-(

                        // implementation notes:
                        // 1) Native NodeList is not an array, and cannot be used directly
                        // in concat() --- the latter doesn't recognize it as an array, and
                        // does not inline it, but append as a single entity.
                        // 2) On some browsers (e.g., Safari) the "constructor" property is
                        // read-only and cannot be changed. So we have to test for both
                        // native NodeList and dojo.NodeList in this property to recognize
                        // the node list.

                        var t = lang.isArray(this) ? this : aps.call(this, 0),
                                m = array.map(arguments, function(a){
                                        return a && !lang.isArray(a) &&
                                                (typeof NodeList != "undefined" && a.constructor === NodeList || a.constructor === this._NodeListCtor) ?
                                                        aps.call(a, 0) : a;
                                });
                        return this._wrap(apc.apply(t, m), this);       // dojo.NodeList
                },

                map: function(/*Function*/ func, /*Function?*/ obj){
                        // summary:
                        //              see dojo.map(). The primary difference is that the acted-on
                        //              array is implicitly this NodeList and the return is a
                        //              dojo.NodeList (a subclass of Array)
                        ///return d.map(this, func, obj, d.NodeList); // dojo.NodeList
                        return this._wrap(array.map(this, func, obj), this); // dojo.NodeList
                },

                forEach: function(callback, thisObj){
                        // summary:
                        //              see `dojo.forEach()`. The primary difference is that the acted-on
                        //              array is implicitly this NodeList. If you want the option to break out
                        //              of the forEach loop, use every() or some() instead.
                        forEach(this, callback, thisObj);
                        // non-standard return to allow easier chaining
                        return this; // dojo.NodeList
                },
                filter: function(/*String|Function*/ filter){
                        // summary:
                        //              "masks" the built-in javascript filter() method (supported
                        //              in Dojo via `dojo.filter`) to support passing a simple
                        //              string filter in addition to supporting filtering function
                        //              objects.
                        // filter:
                        //              If a string, a CSS rule like ".thinger" or "div > span".
                        // example:
                        //              "regular" JS filter syntax as exposed in dojo.filter:
                        //              |       dojo.query("*").filter(function(item){
                        //              |               // highlight every paragraph
                        //              |               return (item.nodeName == "p");
                        //              |       }).style("backgroundColor", "yellow");
                        // example:
                        //              the same filtering using a CSS selector
                        //              |       dojo.query("*").filter("p").styles("backgroundColor", "yellow");

                        var a = arguments, items = this, start = 0;
                        if(typeof filter == "string"){ // inline'd type check
                                items = query._filterResult(this, a[0]);
                                if(a.length == 1){
                                        // if we only got a string query, pass back the filtered results
                                        return items._stash(this); // dojo.NodeList
                                }
                                // if we got a callback, run it over the filtered items
                                start = 1;
                        }
                        return this._wrap(array.filter(items, a[start], a[start + 1]), this);   // dojo.NodeList
                },
                instantiate: function(/*String|Object*/ declaredClass, /*Object?*/ properties){
                        // summary:
                        //              Create a new instance of a specified class, using the
                        //              specified properties and each node in the nodeList as a
                        //              srcNodeRef.
                        // example:
                        //              Grabs all buttons in the page and converts them to diji.form.Buttons.
                        //      |       var buttons = dojo.query("button").instantiate("dijit.form.Button", {showLabel: true});
                        var c = lang.isFunction(declaredClass) ? declaredClass : lang.getObject(declaredClass);
                        properties = properties || {};
                        return this.forEach(function(node){
                                new c(properties, node);
                        });     // dojo.NodeList
                },
                at: function(/*===== index =====*/){
                        // summary:
                        //              Returns a new NodeList comprised of items in this NodeList
                        //              at the given index or indices.
                        //
                        // index: Integer...
                        //              One or more 0-based indices of items in the current
                        //              NodeList. A negative index will start at the end of the
                        //              list and go backwards.
                        //
                        // example:
                        //      Shorten the list to the first, second, and third elements
                        //      |       dojo.query("a").at(0, 1, 2).forEach(fn);
                        //
                        // example:
                        //      Retrieve the first and last elements of a unordered list:
                        //      |       dojo.query("ul > li").at(0, -1).forEach(cb);
                        //
                        // example:
                        //      Do something for the first element only, but end() out back to
                        //      the original list and continue chaining:
                        //      |       dojo.query("a").at(0).onclick(fn).end().forEach(function(n){
                        //      |               console.log(n); // all anchors on the page.
                        //      |       })
                        //
                        // returns:
                        //              dojo.NodeList
                        var t = new this._NodeListCtor(0);
                        forEach(arguments, function(i){
                                if(i < 0){ i = this.length + i; }
                                if(this[i]){ t.push(this[i]); }
                        }, this);
                        return t._stash(this); // dojo.NodeList
                }
        });


/*===== 
dojo.query = function(selector, context){
        // summary:
        //              This modules provides DOM querying functionality. The module export is a function
        //              that can be used to query for DOM nodes by CSS selector and returns a dojo.NodeList
        //              representing the matching nodes.
        //
        // selector: String
        //              A CSS selector to search for.
        // context: String|DomNode?
        //              An optional context to limit the searching scope. Only nodes under `context` will be 
        //              scanned. 
        // 
        //      example:
        //              add an onclick handler to every submit button in the document
        //              which causes the form to be sent via Ajax instead:
        //      |       define(["dojo/query"], function(query){
        //      |       query("input[type='submit']").on("click", function(e){
        //      |               dojo.stopEvent(e); // prevent sending the form
        //      |               var btn = e.target;
        //      |               dojo.xhrPost({
        //      |                       form: btn.form,
        //      |                       load: function(data){
        //      |                               // replace the form with the response
        //      |                               var div = dojo.doc.createElement("div");
        //      |                               dojo.place(div, btn.form, "after");
        //      |                               div.innerHTML = data;
        //      |                               dojo.style(btn.form, "display", "none");
        //      |                       }
        //      |               });
        //      |       }); 
        //
        // description:
        //              dojo/query is responsible for loading the appropriate query engine and wrapping 
        //              its results with a `dojo.NodeList`. You can use dojo/query with a specific selector engine
        //              by using it as a plugin. For example, if you installed the sizzle package, you could
        //              use it as the selector engine with:
        //              |       define("dojo/query!sizzle", function(query){
        //              |               query("div")...
        //
        //              The id after the ! can be a module id of the selector engine or one of the following values:
        //              |       + acme: This is the default engine used by Dojo base, and will ensure that the full
        //              |       Acme engine is always loaded. 
        //              |       
        //              |       + css2: If the browser has a native selector engine, this will be used, otherwise a
        //              |       very minimal lightweight selector engine will be loaded that can do simple CSS2 selectors
        //              |       (by #id, .class, tag, and [name=value] attributes, with standard child or descendant (>)
        //              |       operators) and nothing more.
        //              |
        //              |       + css2.1: If the browser has a native selector engine, this will be used, otherwise the
        //              |       full Acme engine will be loaded. 
        //              |       
        //              |       + css3: If the browser has a native selector engine with support for CSS3 pseudo
        //              |       selectors (most modern browsers except IE8), this will be used, otherwise the
        //              |       full Acme engine will be loaded.
        //              |       
        //              |       + Or the module id of a selector engine can be used to explicitly choose the selector engine
        //              
        //              For example, if you are using CSS3 pseudo selectors in module, you can specify that
        //              you will need support them with:
        //              |       define("dojo/query!css3", function(query){
        //              |               query('#t > h3:nth-child(odd)')...
        //
        //              You can also choose the selector engine/load configuration by setting the <FIXME:what is the configuration setting?>.
        //              For example:
        //              |       <script data-dojo-config="query-selector:'css3'" src="dojo.js"></script>
        //              
        return new dojo.NodeList(); // dojo.NodeList
};
=====*/

function queryForEngine(engine, NodeList){
        var query = function(/*String*/ query, /*String|DOMNode?*/ root){
                //      summary:
                //              Returns nodes which match the given CSS selector, searching the
                //              entire document by default but optionally taking a node to scope
                //              the search by. Returns an instance of dojo.NodeList.
                if(typeof root == "string"){
                        root = dom.byId(root);
                        if(!root){
                                return new NodeList([]);
                        }
                }
                var results = typeof query == "string" ? engine(query, root) : query.orphan ? query : [query];
                if(results.orphan){
                        // already wrapped
                        return results; 
                }
                return new NodeList(results);
        };
        query.matches = engine.match || function(node, selector, root){
                // summary:
                //              Test to see if a node matches a selector
                return query.filter([node], selector, root).length > 0;
        };
        // the engine provides a filtering function, use it to for matching
        query.filter = engine.filter || function(nodes, selector, root){
                // summary:
                //              Filters an array of nodes. Note that this does not guarantee to return a dojo.NodeList, just an array.
                return query(selector, root).filter(function(node){
                        return array.indexOf(nodes, node) > -1;
                });
        };
        if(typeof engine != "function"){
                var search = engine.search;
                engine = function(selector, root){
                        // Slick does it backwards (or everyone else does it backwards, probably the latter)
                        return search(root || document, selector);
                };
        }
        return query;
}
var query = queryForEngine(defaultEngine, NodeList);
// the query that is returned from this module is slightly different than dojo.query,
// because dojo.query has to maintain backwards compatibility with returning a
// true array which has performance problems. The query returned from the module
// does not use true arrays, but rather inherits from Array, making it much faster to
// instantiate.
dojo.query = queryForEngine(defaultEngine, function(array){
        // call it without the new operator to invoke the back-compat behavior that returns a true array
        return NodeList(array);
});

query.load = /*===== dojo.query.load= ======*/ function(id, parentRequire, loaded, config){
        // summary: can be used as AMD plugin to conditionally load new query engine
        // example:
        //      |       define(["dojo/query!custom"], function(qsa){ 
        //      |               // loaded selector/custom.js as engine
        //      |               qsa("#foobar").forEach(...);
        //      |       });
        loader.load(id, parentRequire, function(engine){
                loaded(queryForEngine(engine, NodeList));
        });
};

dojo._filterQueryResult = query._filterResult = function(nodes, selector, root){
        return new NodeList(query.filter(nodes, selector, root));
};
dojo.NodeList = query.NodeList = NodeList;
return query;
});