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---
id: 587d7b8b367417b2b2512b53
title: Use class Syntax to Define a Constructor Function
challengeType: 1
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forumTopicId: 301212
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---
## Description
<section id='description'>
ES6 provides a new syntax to help create objects, using the keyword <dfn>class</dfn>.
This is to be noted, that the <code>class</code> syntax is just a syntax, and not a full-fledged class based implementation of object oriented paradigm, unlike in languages like Java, or Python, or Ruby etc.
In ES5, we usually define a constructor function, and use the <code>new</code> keyword to instantiate an object.
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```js
var SpaceShuttle = function(targetPlanet){
this.targetPlanet = targetPlanet;
}
var zeus = new SpaceShuttle('Jupiter');
```
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The class syntax simply replaces the constructor function creation:
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```js
class SpaceShuttle {
constructor(targetPlanet) {
this.targetPlanet = targetPlanet;
}
}
const zeus = new SpaceShuttle('Jupiter');
```
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Notice that the <code>class</code> keyword declares a new function, and a constructor was added, which would be invoked when <code>new</code> is called - to create a new object.<br>
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<strong>Notes:</strong><br><ul>
<li> UpperCamelCase should be used by convention for ES6 class names, as in <code>SpaceShuttle</code> used above.</li>
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<li> The constructor method is a special method for creating and initializing an object created with a class. You will learn more about it in the Object Oriented Programming section of the JavaScript Algorithms And Data Structures Certification.</li></ul>
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</section>
## Instructions
<section id='instructions'>
Use <code>class</code> keyword and write a proper constructor to create the <code>Vegetable</code> class.
The <code>Vegetable</code> lets you create a vegetable object, with a property <code>name</code>, to be passed to constructor.
</section>
## Tests
<section id='tests'>
```yml
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tests:
- text: <code>Vegetable</code> should be a <code>class</code> with a defined <code>constructor</code> method.
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testString: assert(typeof Vegetable === 'function' && typeof Vegetable.constructor === 'function');
- text: <code>class</code> keyword should be used.
testString: assert(code.match(/class/g));
- text: <code>Vegetable</code> should be able to be instantiated.
testString: assert(() => {const a = new Vegetable("apple"); return typeof a === 'object';});
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- text: <code>carrot.name</code> should return <code>carrot</code>.
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testString: assert(carrot.name=='carrot');
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```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
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/* Alter code below this line */
/* Alter code above this line */
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const carrot = new Vegetable('carrot');
console.log(carrot.name); // => should be 'carrot'
```
</div>
</section>
## Solution
<section id='solution'>
```js
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class Vegetable {
constructor(name) {
this.name = name;
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}
}
const carrot = new Vegetable('carrot');
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```
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</section>