p = {"o":1,"z":2,"z2":3}
k = {"o":1}
k.z = function handlerFactory() {

            return { test: 

                 function () { return "4"; } };

            }
k.z() = [object Object]
k.z().test() = "4"
k.z().test()+1 = "41"

sibling with block
k.z2 = function handlerFactory2() {

                return {

                    test:

                         function a() { return "5"; }

                };

            }
k.z2() = [object Object]
k.z2().test() = "5"
k.z2().test()+1 = "51"

compat mode specifics as !== undefined (if present) - version:2 specifics