我的模块加载系统 v6

模块系统是我框架的核心模块的一部分，与domReady彻底地整合在一起。当然核心模块还提供了其他常用方法，如数组化，类型判定，简单的事件绑定...本版本主要是对类型判定进行优化与重写模块加载，以更优雅的方式处置循环依赖的问题。

(function(global,DOC){
    var
    _dom = global.dom,
    hash = "#",
    namespace = escape(DOC.URL.split(hash)[0]),
    HEAD = DOC.head || DOC.getElementsByTagName("head")[0],
    class2type = {
        "[object HTMLDocument]"   : "Document",
        "[object HTMLCollection]" : "NodeList",
        "[object StaticNodeList]" : "NodeList",
        "[object IXMLDOMNodeList]": "NodeList",
        "[object DOMWindow]"      : "Window"  ,
        "null"                    : "Null"    ,
        "NaN"                     : "NaN"     ,
        "undefined"               : "Undefined"
    },
    toString = class2type.toString;
    /**
     * 糅杂，为一个对象添加更多成员
     * @param {Object} target 目标对象
     * @param {Object} source 属性包
     * @param {Boolean|undefined} override
     * @return  {Object} 目标对象
     */
    function mix(target, source, override) {
        var key,  ride = (override === void 0) || override;
        for (key in source) {
            if (ride || !(key in target)) {
                target[key] = source[key];
            }
        }
        return target;
    }
    /**
     * @class dom
     * dom Framework拥有两个命名空间,
     * 第一个是escape(DOC.URL.split("#")[0])，根据页面的地址动态生成
     * 第二个是dom，我们可以使用别名机制重写它
     * @namespace dom
     */
    var dom = function(expr,context){
        if(typeof expr === "function"){
            dom.ready(expr, true);
        }else{
            if(!dom.fn)
                throw "must load the 'node' module!"
            return new dom.fn.init(expr,context);
        }      
    }
 
    mix(dom,{
        uuid:1,
        HTML:DOC.documentElement,
        HEAD:HEAD,
        rword:/[^, ]+/g,
        rreadystate: /loaded|complete|undefined/i,
        "@name":"dom",
        "@debug":true,
        "@emitter": DOC.dispatchEvent ? "addEventListener" : "attachEvent",
        /**
         * 别名机制(相当于jquery的noConflict)
         * @param {String} name 新的命名空间
         */
        exports: function(name) {
            _dom && (global.dom = _dom);
            name = name || dom["@name"];
            dom["@name"] = name ;
            global[name] = global[namespace] = this;
        },
        /**
         * 数组化
         * @param {ArrayLike} nodes 要处理的类数组对象
         * @param {Number} start 可选。要抽取的片断的起始下标。如果是负数，从后面取起
         * @param {Number} end  可选。规定从何处结束选取
         * @return {Array}
         */
        slice: function (nodes, start, end) {
            for(var i = 0,n = nodes.length, result = []; i < n; i++){
                result[i] = nodes[i];
            }
            if (arguments.length > 1) {
                return result.slice(start , (end || result.length));
            } else {
                return result;
            }
        },
        /**
         * curry化
         * @param {Any} a
         * @return {Function} 新函数
         */
        K:function (a) {
            return function() {
                return a;
            };
        },
        /**
         * 用于取得数据的类型或判定数据的类型
         * @param {Any} obj 要检测的东西
         * @param {String} str 要比较的类型
         * @return {String|Boolean}
         */
        type : function(obj, str){
            var result = class2type[ (obj == null || obj !== obj )? String(obj) :  toString.call(obj)  ] || obj.nodeName || hash;
            if( result.charAt(0) === hash){//兼容旧式浏览器与处理个别情况,如window.opera
                if(obj.window==obj){
                    result = 'Window'; //返回构造器名字
                }else if(obj.nodeType === 9) {
                    result = 'Document';//返回构造器名字
                }else if(  obj.callee ){
                    result = 'Arguments';//返回构造器名字
                }else if(isFinite(obj.length) && obj.item ){
                    result = 'NodeList';//处理节点集合
                }else if(obj.open && obj.send ){
                    result = "XMLHttpRequest";
                }else{
                    result = toString.call(obj).slice(8,-1);
                }
            }
            if(str){
                return str === result;
            }
            return result;
        },
   
        /**
         * 用于调试
         * @param {String} s
         */
        log:function(s){
            global.console && global.console.log(s);
        },
        /**
         * 生成键值统一的对象，用于高速化判定
         * @param {Array} array
         * @param {Number} val 可选，默认为1
         * @return {Object}
         */
        oneObject : function(array, val){
            if(typeof array == "string"){
                array = array.match(dom.rword) || []
            }
            var result = {},value = val !== void 0 ? val :1;
            for(var i=0,n=array.length;i < n;i++){
                result[array[i]] = value;
            }
            return result;
        }
    });
    "Boolean,Number,String,Function,Array,Date,RegExp,Window,Document,Arguments,NodeList,XMLHttpRequest".replace(dom.rword,function(name){
        class2type[ "[object " + name + "]" ] = name;
    });
 
    // http://wp.moooori.com/archives/1911
    var
    rmodule =  /([^(\s]+)\(?([^)]*)\)?/,
    //  rreadystate = /loaded|complete|undefined/i,
    method = DOC.dispatchEvent ? "onload" : "onreadystatechange",
    stack = [],//用于放置负回调
    checks = [],//用于放置正向回调或模块本身的wrapper函数
    status = {};//用于记录每个模块加载状态0 未注册 1 已注册 2 已加载 3已执行
    /**
     * 用于模拟opera的script onerror
     * http://d.hatena.ne.jp/NeoCat/20110206/1296934235
     * @param {String} name 模块名
     * @param {String} url  模块的路径
     * @param {Element} node 为加载这个模块临时生成的script节点
     */
    function fixOperaError(name, url, node){
        var iframe = DOC.createElement("iframe");
        var code = '<script src="'+dom.baseURL+'"><\/script>'+
            '<script src="'+url+'" onload="this.ownerDocument.x = 1"><\/script>';
        iframe.style.display = "none";
        HEAD.appendChild(iframe);
        var d = iframe.contentDocument;
        iframe.onload = function(){
            if(d.x == void 0){
                removeScript(name, node, true);
            }
            iframe.onload = null;//opera无法在iframe被事件绑定时被移除
            HEAD.removeChild(this);
        };
        try{
            d.write(code);
            d.close();
        }catch(e){};
    }
    //执行并移除所有依赖都具备的模块或回调
    function resolveCallbacks(){
        for(var i = 0, obj; i < checks.length; i++){
            obj = checks[i];
            for(var name in status){
                if(status[name] == 3 && obj.deps["@"+name]){
                    delete obj.deps["@"+name];
                    obj.length--;
                    dom["@debug"] &&  dom.log(obj.length+" "+name);
                }
            }
            if(!obj.length){
                obj.callback()
                checks.splice(i--,1);
            }
        }
    }
    /**
     * 为加载模块而临时生成一个script节点
     * @param {String} name 模块名
     * @param {String} url  模块的路径
     */
    function appendScript(name, url){
        var node = DOC.createElement("script");
        url = url  || dom.basePath +"/"+ name + ".js" + (dom.DEBUG ? "?t="+new Date : "");
        node.charset = "utf-8";
        node.async = true;
        node.onerror = function(){
            removeScript(name, this, true);
        }
        node[method] = function(){
            if (dom.rreadystate.test(this.readyState) ){
                for(var i =0 ; i < checks.length ;i++){
                    resolveCallbacks()
                }
                removeScript(name, this );
            }
        }
        node.src =  url+"?timestamp="+(+new Date);
        global.opera && fixOperaError(name, url, node);
        HEAD.insertBefore(node,HEAD.firstChild);
    }
    /**
     * 移除临时生成的script节点
     * @param {String} name 模块名
     * @param {Element} node 为加载这个模块临时生成的script节点
     * @param {Boolean} error 是否加载失败
     */
    function removeScript(name, node, error){
        var parent = node.parentNode;
        if(parent && parent.nodeType === 1){
            if(error || status[name] === 1){
                dom.stack('dom.log("fail to load module [ '+name+' ]")');
                dom.stack(true);//打印错误堆栈
            }
            if (node.clearAttributes) {
                node.clearAttributes();
            } else {
                node[method] = node.onerror = null;
            }
            parent.removeChild(node);
        }
    }
 
    mix(dom, {
        mix:mix,
        //绑定事件(简化版)
        bind : DOC.dispatchEvent ? function(el, type, fn, phase){
            el.addEventListener(type,fn, phase);
        } : function(el, type, fn){
            el.attachEvent("on"+type, function(){
                fn.call(el,event);
            });
        },
        stack:function(fn){
            if(fn === true){
                while(fn = stack.pop()){
                    fn();
                }
            }else if(typeof fn === "string"){
                stack.push(new Function(fn));
            }else if(typeof fn === "function"){
                stack.push(fn);
            }
        },
        /**
         * <a href="http://www.cnblogs.com/rubylouvre/archive/2011/02/10/1950940.html">核心模块所在路径</a>
         * @property
         * @type String
         */
        basePath:(function(url, scripts, node){
            scripts = DOC.getElementsByTagName("script");
            node = scripts[scripts.length - 1]
            url = node.hasAttribute ?  node.src : node.getAttribute('src', 4);
            dom.baseURL = url;
            return url.substr( 0, url.lastIndexOf('/'));
        })(),
        /**
         * 请求模块
         * @param {String|Array} deps 依赖列表，如果是字符串请用逗号隔开，如果要指定具体路径请写到小括号中
         * @param {Function} module 正向回调
         * @param {Function} errback 负向回调
         * @param {Boolean} ready 是否延迟到DOM树建完才执行回调函数
         */
        require:function(deps,callback,errback){
            var names = [];
            (deps +"").replace(dom.rword,function(url,name,match){
                match = url.match(rmodule);
                name  = match[1];
                if(!status[name]){ //防止重复生成节点与请求
                    status[name] = 1;
                    if(name !== "ready"){
                        appendScript(name,match[2]);//加载JS文件
                        dom.stack(errback);//压入错误堆栈
                    }
                }
                if(!names["@"+name]){//防止"node,oop,node"的情况
                    names.push(name);
                    names["@"+name] = 1;
                }
            });
            this.provide(names,callback);
        },
        /**
         * 定义模块
         * @param {String} name 模块名
         * @param {String} dependList 依赖列表
         * @param {Function} module 模块本身
         */
        define:function(name,deps,callback){
            if(typeof deps == "function"){//处理只有两个参数的情况
                callback = deps;
                deps = "";
            }
            status[name] = 2;
            function wrap(){
                status[name] = 3;
                //这里必须把已添加了新能力的dom命名空间对象传入去,放便其他模块第一时间能使用这些新能力
                callback();
            }
            wrap._name = name;
            //如果是空字符串则置换为空数组
            this.require(deps,wrap);
   
        },
        /**
         * 装配模块
         * @param {Array} array 模块列表
         * @param {Function} callback 回调函数
         */
        provide:function(names,callback){ 
            checks.unshift({
                name:callback._name || "",
                callback:callback,
                deps:names,
                length:names.length
            });  
        }
    });
    /**
     * domReady机制
     * @param {Function} fn 回调函数
     * @param {Boolean} more 是否加载指定的模块
     */
    var Ready = dom.ready = function(fn){
        if ( Ready.list) {
            Ready.list.push( fn );
        }else{
            fn();
        }
    };
    Ready.list = [];
    function fireReady(){
        if(Ready.list){
            for(var i=0, fn;fn = Ready.list[i++];)
                fn();
            status.ready = 3;
            delete Ready.list;
        }
    };
    function doScrollCheck() {
        try {
            dom.HTML.doScroll("left");
            fireReady();
        } catch(e) {
            setTimeout( doScrollCheck, 0);
        }
    };
    //开始判定页面的加载情况
    if ( DOC.readyState === "complete" ) {
        fireReady();
    }else {
        dom.bind(DOC, (DOC.dispatchEvent ? "DOMContentLoaded" : "readystatechange"), function(){
            if (DOC.dispatchEvent || DOC.readyState === "complete") {
                fireReady();
            }
        });
        try {
            //http://bugs.jquery.com/ticket/4787 http://cmc3.cn/
            //在IE6下,内嵌页面如果重设了document.domain，访问window.frameElement抛错，
            //但是经过多次try catch后，才能访问该值
            var toplevel = global.frameElement == null;
        } catch(e) {};
        if ( dom.HTML.doScroll && toplevel ) {
            doScrollCheck();
        }
    }
    dom.exports();
})(this,this.document);
//2011.7.11
//@开头的为私有的系统变量，防止人们直接调用
//dom.check改为dom["@emitter"]
//dom.namespace改为dom["@name"]
//去掉无用的dom.modules
//优化exports方法

每个模块的定义如下(请确保模块名与文件名要一致)：

(function(global,DOC){
    var dom = global[escape(DOC.URL.split("#")[0])];
    dom.define("class", "lang",function(){
       dom.log("class模块")
    });
 
})(this,this.document);

使用：

//这里的回调函数会class模块加载后，并且待到domReady之后执行。
//http://www.cnblogs.com/rubylouvre/archive/2011/07/12/2104777.html by 司徒正美
      dom.require("class,ready",function(){    
         alert(1000)
      });
相关链接我的模块加载系统 v5