I'm trying to call a function of the object from another function and I get "Undefined is not a function" error. I think there's some silly mistake but I can't figure it out.
function dataProvider() {
    var self = this;
    self.loadData = ko.computed(function(){
        var data = new Data(self.getJson().data); //here comes the error
        ...
    });
    self.getJson = function(){
        if(typeof jsonVar !== 'undefined')
            return jsonVar;
        else {
            ...
        }
    };
}
The jsonVar is defined and it is a valid JSON. Data is an object, but self.getJson() just doesn't work.
EDIT: It is not about calling private or public method. The problem is that I can't call the method of the object.
 
    