learning how to add method to function constructor

section4/script.js

@@ -12,7 +12,11 @@ var Person = function(name, yearOfBirth, job) {
   this.name = name;
   this.yearOfBirth = yearOfBirth;
   this.job = job;
+  this.calculateAge = function() {
+      console.log(2019 - this.yearOfBirth);
+  }
 };
 
 var mike = new Person("mike", 1991, "developer");
 console.log(mike);
+mike.calculateAge();