Реализация вызова кастомного метода 'method' у любой ф-ии конструктора

var Person = function(name){ 
  this.name=name; 
} 
Person.method = (name, func) => (Person.prototype[name] = func, Person); 
 
 
Person.method('getName', function () { 
    return this.name; 
  }).method('setSurname', function (surname) { 
    this.surname = surname; 
  }).method('getFullName', function () { 
    return this.surname + ' ' + this.name; 
  }); 
 
var person = new Person('Alex'); 
console.log(person); 
person.setSurname('Sins'); 
console.log(person.getName()); 
console.log(person.getFullName());