let data = {
}
let __name = "saltfish"
let __age  = 19

Object.defineProperty(data,"name",{
    set:function(newVal){
        console.log("set: data.name")
        __name = newVal
        document.getElementById("name").innerText = __name
    },
    get:function () {
        console.log("get: data.name")
        return __name
    }
})

Object.defineProperty(data,"age",{
    set:function(newVal){
        console.log("set: data.age")
        __age = newVal
        document.getElementById("age").innerText = __age
    },
    get:function () {
        console.log("get: data.age")

        return __age
    }
})