es6 functions equivalent code example

Example 1: es6 method definition syntax

const obj = {
  foo() {
    return 'bar';
  }
};

console.log(obj.foo());
// expected output: "bar"

Example 2: es6 class example

var Polygon = class { 
   constructor(height, width) { 
      this.height = height; 
      this.width = width; 
   } 
}