Tarik

In javascript, I'm seeing that complex LiveAPI operations always run into this error:"Javascript TypeError: non-native scope object".

If one tries to apply numerous LiveAPI actions in a short time, errors appear (also when not in edit mode) and the results become unpredictable.

The patch below gives a simple example, where the creation and usage of LiveAPI objects will throw these errors. In this example the errors do not reappear after the first time they've popped up, until the js object is reinitialised. In my much more complex real-life situations though, these errors pop up all over the place at unpredictable times, unfortunately greatly hindering my progress..!

To reproduce, please copy-paste the attached supersimple m4l patch, and put the following code in the js object:

post("creating " + amount + " LiveAPIs\n");

var l =new LiveAPI(["live_set","tracks",0]);

In javascript, I'm seeing that complex LiveAPI operations always run into this error:"Javascript TypeError: non-native scope object".
  If one tries to apply numerous LiveAPI actions in a short time, errors appear (also when not in edit mode) and the results become unpredictable.

  The patch below gives a simple example, where the creation and usage of LiveAPI objects will throw these errors. In this example the errors do not reappear after the first time they've popped up, until the js object is reinitialised. In my much more complex real-life situations though, these errors pop up all over the place at unpredictable times, unfortunately greatly hindering my progress..!

function createLiveAPIs(amount) {
    post("creating " + amount + " LiveAPIs\n");
    for( var i=0; i
        new LiveAPI(["live_set"]);
    }
}

function useLiveAPIs(amount) {
    post("using " + amount + " LiveAPIs\n");
    var l =new LiveAPI(["live_set","tracks",0]);
    for( var i=0; i
        l.get("name");
    }
}


js-liveapi-object-bug

So... reproduced this a couple of times now on different computers and versions:

OSX 10.9.5, 2.7 GHz Intel Core i7 Macbook Pro

Live 9.1.5 (64 bit) and Live 9.1.6 (32 bit and 64 bit) 

OSX 10.9.5, 3.5 GHz 6-Core Intel Xeon E5 Mac Pro

Errors occur both in edit and non-edit mode...

EDIT: i now see that in my more complex javascript objects, the occurrence of this error seems to be related to the most absurd factors, like if there's an unrelated for-loop that does nothing with any LiveAPI object, but occurs directly after doing a LiveAPI action, it will influence the occurrence of the error. This bug is a weird one!

EDIT2: Today I saw the error occur without ANY LiveAPI actions. I'm starting to believe the bug is only triggered, not caused, by the LiveAPI. Something to do with general JS performance/threading in M4L perhaps?

OSX 10.9.5, 2.7 GHz Intel Core i7 Macbook Pro
Live 9.1.5 (64 bit) and Live 9.1.6 (32 bit and 64 bit) 
Max 6.1.7 and Max 7.0.0

OSX 10.9.5, 3.5 GHz 6-Core Intel Xeon E5 Mac Pro
Live 9.1.5 (64 bit)
Max 6.1.7 and Max 7.0.0

EDIT2: Today I saw the error occur without ANY LiveAPI actions. I'm starting to believe the bug is only triggered, not caused, by the LiveAPI. Something to do with general JS performance/threading in M4L perhaps?


bump, cause this is a general problem popping up EVERYWHERE in my js code, disrupts its execution, and may reveal an important issue with javascript within M4L.

Hi, why are you passing array objects into the LiveAPI constructor? This works fine for me:

autowatch = 1;
post("js file loaded");

function createLiveAPIs(amount) {
    post("creating " + amount + " LiveAPIs\n");
    for (var i = 0; i < amount; i++) { // the error will appear even with numbers as low as 50
        new LiveAPI("live_set");
    }
}

function useLiveAPIs(amount) {
    post("using " + amount + " LiveAPIs\n");
    var l = new LiveAPI("live_set tracks 0");
    for (var i = 0; i < amount; i++) { // the error will appear even with numbers as low as 50
        l.get("name");
    }
}


autowatch = 1;
post("js file loaded");

function createLiveAPIs(amount) {
	post("creating " + amount + " LiveAPIs\n");
	for (var i = 0; i < amount; i++) { // the error will appear even with numbers as low as 50
		new LiveAPI("live_set");
	}
}

function useLiveAPIs(amount) {
	post("using " + amount + " LiveAPIs\n");
	var l = new LiveAPI("live_set tracks 0");
	for (var i = 0; i < amount; i++) { // the error will appear even with numbers as low as 50
		l.get("name");
	}
}


Jeremy, thanks so much! It looks like the arrays indeed were the problem.

I was passing arrays because LiveAPI ".get" methods return arrays which I sometimes use to instantiate new LiveAPI objects. Example:

var liveSet =  new LiveAPI("live_set");
var master = new LiveAPI(liveSet.get("master_track")); // 'get' returns an array

...but now it seems I need to convert the array to a string delineated with spaces before I use the result of 'get'.

I was passing arrays because LiveAPI ".get" methods return arrays which I sometimes use to instantiate new LiveAPI objects. Example: 

...but now it seems I need to convert the array to a string delineated with spaces before I use the result of 'get'.


I think this may in fact be a bug -- I added this array junk at some point (don't remember why anymore) and the object is supposed to gracefully convert back and forth from arrays and strings. But the workaround is easy enough until we've had a chance to isolate and fix the problem.

Thanks again, its always good to know that its not just me being silly!

its 2020 and the problem seems still to be persistent ;-)

//One needs still to do the followingin in order to avoid "non-native scope object"-Exception

var selectedTrackId = livesetView.get('selected_track');

var selectedTrackIdJoined = selectedTrackId.join(' ');

var api = new LiveAPI(selectedTrackIdJoined);

Hey :-) 
its 2020 and the problem seems still to be persistent  ;-)
 I am on Win 10 Pro, vers. 1903, Max 8

//One needs still to do the followingin in order to avoid "non-native scope object"-Exception
var selectedTrackId = livesetView.get('selected_track');
var selectedTrackIdJoined = selectedTrackId.join(' ');
var api = new LiveAPI(selectedTrackIdJoined);


Hey, I'd like to help, but I cannot reproduce on my system (I'm on macOS, but it shouldn't make a difference). Here's my js source (in the future, please post complete source if you want us to be able to quickly investigate a report):

autowatch =1;

//One needs still to do the followingin in order to avoid "non-native scope object"-Exception
function bang() {
    var livesetView = new LiveAPI('live_set view');
    var selectedTrackId = livesetView.get('selected_track');
    post("selectedTackId isArray()? " + Array.isArray(selectedTrackId) + "\n");
    var selectedTrackIdJoined = selectedTrackId.join(' ');

    var api2 = new LiveAPI(selectedTrackId);
    post("unjoined: " + api2.id + "\n");

    var api = new LiveAPI(selectedTrackIdJoined);
    post("joined: " + api.id + "\n");

}

autowatch =1;

//One needs still to do the followingin in order to avoid "non-native scope object"-Exception
function bang() {
	var livesetView = new LiveAPI('live_set view');
	var selectedTrackId = livesetView.get('selected_track');
	post("selectedTackId isArray()? " + Array.isArray(selectedTrackId) + "\n");
	var selectedTrackIdJoined = selectedTrackId.join(' ');

	var api2 = new LiveAPI(selectedTrackId);
	post("unjoined: " + api2.id + "\n");

	var api = new LiveAPI(selectedTrackIdJoined);
	post("joined: " + api.id + "\n");

}

Thanks for your reply! My code works I just wanted to say that the problem still persist and I posted a slim snipped in order to help others but thanks anyway :-)

Thanks for your reply! My code works I just wanted to say that the problem still persist and I posted a slim snipped in order to help others but thanks  anyway :-)

EDIT: I can reproduce it with some effort, in fact. Thanks for bringing it to my attention.

@sysex : I'm not sure what problem you're talking about, in that case. This thread was about a problem with the LiveAPI object not properly parsing arrays, which was fixed.

To me the solution was too much hidden in the communication. Thats why I wanted to make it stand out for others who just want to get back coding quickly ;-)

Bottomline: Join the Array returned from the call of 'selected_track' in order to pass it to another LiveAPI Object constructor to obtain the actuall 'Track' object.

To me the solution was too much hidden in the communication. Thats why I wanted to make it stand out for others who just want to get back coding quickly  ;-)

Bottomline: Join the Array returned from the call of 'selected_track' in order to pass it to another LiveAPI Object constructor to obtain the actuall 'Track' object.


Js LiveAPI object bug!