q

With Q I can define a new promise with: var queue = q(); But with Bluebird if I do: var queue = new Promise(); I get: TypeError: the promise constructor requires a resolver function How can I get the same result that I had with Q? This is a snippet of my code: var queue = q() promises = []; queue = queue.then(function () { return Main.gitControl.gitAdd(fileObj.filename, updateIndex); }); // Here more promises are added to queue in the same way used above... promises.push(queue); return Promise.all(promises).then(function () { // ... }); var resolver = Promise.defer(); setTimeout(function() {

I'm looking into BreezeJs and there samples are using Q.js for promises to handle asynchronous calls. John Papa is also using Q. JQuery has promises as well . What are the differences between the two? Bergi Both are based on the Promises/A standard and implement a then method (though only current jQuery, they once had a incompatible pipe instead of then ). However, there are a few differences: Q has exception handling. All thrown errors in the async then callbacks will be caught and reject the promise (and will only get re-thrown if you call .end() ). Not sure whether I personally like that.

Here are some simple questions based on behaviour I noticed in the following example running in node: Q('THING 1').then(console.log.bind(console)); console.log('THING 2'); The output for this is: > "THING 2" > "THING 1" Questions: 1) Why is Q implemented to wait before running the callback on a value that is immediately known? Why isn't Q smart enough to allow the first line to synchronously issue its output before the 2nd line runs? 2) What is the time lapse between "THING 2" and "THING 1" being output? Is it a single process tick? 3) Could there be performance concerns with values that are

I'm using Q for promises, but when setting up some tests I discover I see way in catching async errors thrown inside a function that returns a promise. I tried to wrap it inside a Q.when and chained a fail and or as below a Q.fcall and a chained fail ,but I can't get it to work. var func = function(){ var deferred = Q.defer(); setTimeout(function(){ throw new Error("async error"); },100); return deferred.promise; } Q.fcall(func) .then(function(){ console.log("success"); }) .fail(function(err){ console.log(err); }) Is there a way to to this? The exception in the setTimeout is not related anyhow

EDIT The first answer is the elegant one, but, as stated a few times in this question and another questions on stackoverflow, the problem is that the service and the controller run their thing before the data actually arrives. (Last comment on the first answer:) Yes, the problem is that the API calls finish AFTER the service runs and returns everything to the controller, see here screencast.com/t/uRKMZ1IgGpb7 ... That's my BASE question, how could I wait on all the parts for the data to arrive? It's like I'm saying it on repeat, how do we make a service that populates the array after the