Oliver Eyton-Williams 0bd52f8bd1
Feat: add new Markdown parser (#39800)
and change all the challenges to new `md` format.
2020-11-27 10:02:05 -08:00

1.6 KiB

id, title, challengeType, forumTopicId
id title challengeType forumTopicId
587d7dad367417b2b2512b78 Use a Constructor to Create Objects 1 18233

--description--

Here's the Bird constructor from the previous challenge:

function Bird() {
  this.name = "Albert";
  this.color  = "blue";
  this.numLegs = 2;
  // "this" inside the constructor always refers to the object being created
}

let blueBird = new Bird();

Notice that the new operator is used when calling a constructor. This tells JavaScript to create a new instance of Bird called blueBird. Without the new operator, this inside the constructor would not point to the newly created object, giving unexpected results. Now blueBird has all the properties defined inside the Bird constructor:

blueBird.name; // => Albert
blueBird.color; // => blue
blueBird.numLegs; // => 2

Just like any other object, its properties can be accessed and modified:

blueBird.name = 'Elvira';
blueBird.name; // => Elvira

--instructions--

Use the Dog constructor from the last lesson to create a new instance of Dog, assigning it to a variable hound.

--hints--

hound should be created using the Dog constructor.

assert(hound instanceof Dog);

Your code should use the new operator to create an instance of Dog.

assert(code.match(/new/g));

--seed--

--seed-contents--

function Dog() {
  this.name = "Rupert";
  this.color = "brown";
  this.numLegs = 4;
}
// Only change code below this line

--solutions--

function Dog() {
  this.name = "Rupert";
  this.color = "brown";
  this.numLegs = 4;
}
const hound = new Dog();