exec: how-do-you-create-a-constructor-function

Author: tahachm

questions/how-do-you-create-a-constructor-function/en-US.mdx

@@ -6,13 +6,14 @@ title: How do you create a constructor function?
 
 To create a constructor function in JavaScript, define a regular function with a capitalized name to indicate it's a constructor. Use the `this` keyword to set properties and methods. When creating an instance, use the `new` keyword.
 
-```js
+```js live
 function Person(name, age) {
   this.name = name;
   this.age = age;
 }
 
 const john = new Person('John', 30);
+console.log(john.age); // 30
 ```
 
 ---
@@ -23,7 +24,7 @@ const john = new Person('John', 30);
 
 A constructor function in JavaScript is a regular function that is used to create objects. By convention, the name of the constructor function starts with a capital letter to distinguish it from regular functions.
 
-```js
+```js live
 function Person(name, age) {
   this.name = name;
   this.age = age;
@@ -34,7 +35,7 @@ function Person(name, age) {
 
 Within the constructor function, the `this` keyword is used to refer to the object that will be created. Properties and methods can be assigned to `this`.
 
-```js
+```js live
 function Person(name, age) {
   this.name = name;
   this.age = age;
@@ -50,7 +51,17 @@ function Person(name, age) {
 
 To create an instance of the object, use the `new` keyword followed by the constructor function.
 
-```js
+```js live
+function Person(name, age) {
+  this.name = name;
+  this.age = age;
+  this.greet = function () {
+    console.log(
+      `Hello, my name is ${this.name} and I am ${this.age} years old.`,
+    );
+  };
+}
+
 const john = new Person('John', 30);
 john.greet(); // Output: Hello, my name is John and I am 30 years old.
 ```
@@ -59,7 +70,7 @@ john.greet(); // Output: Hello, my name is John and I am 30 years old.
 
 To save memory, it's a good practice to add methods to the constructor's prototype instead of defining them inside the constructor function.
 
-```js
+```js live
 function Person(name, age) {
   this.name = name;
   this.age = age;
@@ -77,7 +88,13 @@ jane.greet(); // Output: Hello, my name is Jane and I am 25 years old.
 
 You can check if an object is an instance of a constructor function using the `instanceof` operator.
 
-```js
+```js live
+function Person(name, age) {
+  this.name = name;
+  this.age = age;
+}
+const jane = new Person('Jane', 25);
+
 console.log(jane instanceof Person); // Output: true
 ```