JSFiddle - React, Tailwind, and code Playground

JavaScript

var Example = function(){
  this.prop = 'whatever';
}

Example.prototype.fn_1 = function(){
  console.log(this.prop); 
  return this
}

Example.prototype.fn_2 = function(){
  this.prop = 'not whatever';  
  return this
}

var e = new Example();

e.fn_1() //whatever
e.fn_2().fn_1() //not whatever