Is it possible to set argument types in JS functions for code completion?

Kobid

Hi,
For example. When I declare this variable:

function baseHttpRequest(endPoint, onDoneCallback, onErrorCallback) {
        var request = new XMLHttpRequest();
        request.onreadystatechange = function() {
            if (request.readyState === XMLHttpRequest.DONE) {
                if (request.status === 200) {
                    onDoneCallback(request);
                } else {
                    onErrorCallback(request);
                }
            }
        }
    }

Qt Creator in this context know variable type and when I type request. (dot), it suggest object properties etc. But when I pass this object in function argument:

function myFunction( req: XMLHttpRequest ) {
}

then when I type req. I don't see any suggestions which is expected due to JavaScript nature. I'm also getting this warning:
[object Object] should be coerced to void because the function called is insufficiently annotated. The original value is retained. This will change in a future version of Qt
So we must wait or is there any workaround / trick in QML world? My workaround is split wanted values from object as base types:

onErrorCallback(status: int, statustext: string, content: string);

I know that this topic is stupid for java scripters which are used to but I'm "typed" programmer and I like to see types :P