Proper use of "this" in JavaScript objects [duplicate]

In the below example, how can i access enums.ROCK inside the prop? As it currently stand, i get an error Uncaught TypeError: Cannot read property 'enums' of undefined. Plz check comment ERROR LINE.

const app = {  enums: {    ROCK: 'ROCK',    PAPER: 'PAPER',    SCISSORS: 'SCISSORS',    DEFAULT_USER_CHOICE: this.ROCK //default, take note of this keyword  },  prop: {    isGameRunning: false,    mySelection: this.app.enums.ROCK //ERROR LINE  }};

I have tried it with mySelection: app.enums.ROCK as well and in this case i get Uncaught ReferenceError: Cannot access 'app' before initialization.

Sample 1: https://jsfiddle.net/5zp7yode/

Sample 2: https://jsfiddle.net/5zp7yode/1/

Where as the following works without any issues:

var person = {  firstName: "John",  lastName : "Doe",  id       : 5566,  fullName : function() {    return this.firstName +""+ this.lastName;  }};alert(person.fullName());

Sample 3: https://jsfiddle.net/0o93afLq/

I have also tried with following but still can't access enums inside prop:

const app = {  self: this,  enums: {    ROCK: 'ROCK',    PAPER: 'PAPER',    SCISSORS: 'SCISSORS',    DEFAULT_USER_CHOICE: this.ROCK //default, take note of this keyword  },  prop: {    isGameRunning: false,    mySelection: self.enums.ROCK  }};alert(app.prop.mySelection);

Sample 4:https://jsfiddle.net/x89kj2zn/

and another one working with function but i can't call the function inside the prop:

const app = {  enums: {    ROCK: 'ROCK',    PAPER: 'PAPER',    SCISSORS: 'SCISSORS',    DEFAULT_USER_CHOICE: this.ROCK //default, take note of this keyword  },  prop: {    isGameRunning: false  },  getMySelection: function(){    return app.enums.ROCK;  }};alert(app.getMySelection());

Sample 5: https://jsfiddle.net/v5qzdx3s/