javascript 的工具函数

define(function () {
    var now = +new Date();
    var util = {};
    
 
    util.guid = function () {
        return 'e' + now++;
    };
    
   
    util.noop = function () {};
    
    var dontEnumBug = !(({ toString: 1 }).propertyIsEnumerable('toString'));
    
    // type 子类 superType 父类
    util.inherits = function (type, superType) {
        var Empty = function () {};
        Empty.prototype = superType.prototype;
        var proto = new Empty();
    
        var originalPrototype = type.prototype;
        type.prototype = proto;
    
        for (var key in originalPrototype) {
            proto[key] = originalPrototype[key];
        }
        if (dontEnumBug) {
            // 其实还有好多其它的，但应该不会撞上吧(╯‵□′)╯︵┻━┻
            if (originalPrototype.hasOwnProperty('toString')) {
                proto.toString = originalPrototype.toString;
            }
            if (originalPrototype.hasOwnProperty('valueOf')) {
                proto.valueOf = originalPrototype.valueOf;
            }
        }
        type.prototype.constructor = type;
    
        return type;
    };
    
    util.parseJSON = function (text) {
        if (!text) {
            return undefined;
        }
    
        if (window.JSON && typeof JSON.parse === 'function') {
            return JSON.parse(text);
        }
        else {
            /* jshint evil: true */
            return new Function('return (' + text + ');')();
        }
    };
    
    var whitespace = /(^[\s\t\xa0\u3000]+)|([\u3000\xa0\s\t]+$)/g;
    
    util.trim = function (source) {
        return source.replace(whitespace, '');
    };
    
    return util;
});