async：false选项在$.ajax()中不起作用,是否在jQuery 1.8中针对

As of jQuery 1.8,the use of async: false with jqXHR ($.Deferred) is deprecated;
you must use the success/error/complete callback options instead of the corresponding
methods of the jqXHR object such as jqXHR.done() or the deprecated jqXHR.success().

我不知道jqXHR($.Deferred)是什么意思.是因为任何原因使用async：false折旧,还是jqXHR($.Deferred)某种特殊用例？

我问,因为我无法异步地进行$.ajax()调用.这是jQuery 1.8.2：

var ret = {};

$.ajax({
   async:           false,method:         'GET',contentType:    'application/json',dataType:       'jsonp',url:            '/couchDBserver',error:          myerr,success:        function(data) {

        var rows = data.rows;

        //something that takes a long time
        for(var row in rows) {
             ret[rows[row].key] = rows[row].value;
        }

        console.log('tick');
    }
});
console.log('tock');
console.log(JSON.stringify(ret))

我的控制台输出是：

tock
{}
tick

我做错了什么,或者我做错了什么？