那么返回值是如何工作的呢

考虑下面的代码:

function doSomething() {
    var promise = $.ajax(//...);
    return promise;
}

让我们一起使用它 then :

doSomething().then(function(data) {
    return true; // this is passed to the next then
}).then(function(data){
    alert(data); // this will show true as expected
    return doSomething(); // A promise object should be passed to the next then
}).then(function(data){
    // I expected this to be the promise object but this is not a promise object. 
    // It is the response from the doSomething() AJAX call
    alert(data); 
});

问题 当前位置最后一个问题是什么 data 参数是否包含响应?这是怎么回事?