Extract Nested Object Reference.js

/*
Description:
You are given a complex object that has many deeply nested variables. You don't want to go the usual if obj.property == null route. Create a prototype method that given a nested path, either return the value or undefined.

var obj = {
  person: {
    name: 'joe',
    history: {
      hometown: 'bratislava',
      bio: {
        funFact: 'I like fishing.'
      }
    }
  }
};

obj.hash('person.name'); // 'joe'
obj.hash('person.history.bio'); // { funFact: 'I like fishing.' }
obj.hash('person.history.homeStreet'); // undefined
obj.hash('person.animal.pet.needNoseAntEater'); // undefined
*/
Object.prototype.hash = function(string) {
  try {
  return eval(`this.${string}`)
  }
  catch(e){
  return undefined
  }
}