player/js/utils/expressions/PropertyGroupFactory.js

var propertyGroupFactory = (function() {
    return function(interfaceFunction, parentPropertyGroup) {
        return function(val) {
            val = val === undefined ? 1 : val
            if(val <= 0){
                return interfaceFunction;
            } else{
                return parentPropertyGroup(val-1);
            }
        }
    }
}())