Javascript Assert对象链

Question

我在Javascript中有许多子属性和对象的对象。

因此我的代码中的某些行看起来像这样：

  obj.eventOfType = (el.openSocial && el.openSocial.embed && el.openSocial.embed.context &&
                    el.openSocial.embed.context.openSocial && el.openSocial.embed.context.openSocial.connections &&
                    el.openSocial.embed.context.openSocial.connections.generator && el.openSocial.embed.context.openSocial.connections.generator.displayName) ?
                el.openSocial.embed.context.openSocial.connections.generator && el.openSocial.embed.context.openSocial.connections.generator.displayName || "";

看起来不太好..所以我想到了一个函数并写了这个：

    /**
     * assert path exists as subobject chain within obj
     * 
     * @param obj {object} the object to search for <code>path</code> in
     * @param path {String} the path to search within <code>obj</code>. oatgh must not start wirth the object itself.
     * @return {boolean} whether <code>path</code> exists within <code>obj</code> or not
     * example: to check if the windows document body has a fist item element you would use
     * if (assertChain(window, "document.body.firstChild")) {}
     * instead of 
     * if (window && window.document && window.document.body && window.document.body.firstChild) {}
     */
    function assertChain(obj, path) {
        var o = obj,
            ret = ("object" === $.type(obj) && "string" === $.type(path));

        if (ret) {
            $(path.split(".") || {}).each(function(ignore, value) {
                ret = value in o;
                if (ret) {
                    o = o[value];
                }
                return ret;
            });
        }
        return ret;
    }

    var t = assertChain(dataItem, "dataItem.openSocial.embed.context.connectionsContentUrl") && dataItem.openSocial.embed.context.connectionsContentUrl;

    dataItem.xcc = dataItem.xcc || {}; //Access it

所以在Stackoverflow，我发现了这个：

var isDefined = function(value, path) {
  path.split('.').forEach(function(key) { value = value && value[key]; });
  return (typeof value != 'undefined' && value !== null);
};

var t = {a: {a1: 33, a12: {aa1d: 444, cc: 3}}, b: 00};

var results = '';
['a.a12.cc', 'a.a1.cc'].forEach(function(path) {
    results += 't[' + path + '] = ' + isDefined(t, path) + '\n';
});

document.body.appendChild(document.createElement('pre')).textContent = results;

哪种方式最好？