this_ex5.js

const obj = {
  prop: 'Hello',
  method: function() {
    const callback = function() {
       console.log(this.prop + ', World!'); // Hello, World!
    }
    
    setTimeout(callback.bind(this), 2000);
  }
};

obj.method();

/* ------------------------ OR -------------------------------- */

const obj = {
  prop: 'Hello',
  method: function() {
    function inner() {
       console.log(this.prop + ', World!'); // Hello, World!
    }
    
    const innerBind = inner.bind(this);
    
    innerBind();
  }
};

obj.method();