var deferred = $.Deferred();

deferred.then(function(data){
    // new deferred that we will be returning
    var deferred = $.Deferred();
    if (data.success == true) {
        deferred.resolveWith(data.result);
    }
    else {
        deferred.rejectWith(data.error);
    }
    // any following chained methods will affect this returned deferred object
    return deferred;
}).then(
    // done callback
    function(data){
        console.log("Resolved!");
        console.dir(data);
    },
    // fail callback
    function(){
        console.log("Rejected!");
    }
);

var json = $.getJSON("/foo");
json.done(deferred.resolveWith);