constructors

Question 1

Constructors are like regular functions, but we use them with the _______ keyword

Answer 1

new

Question 2

There are two types of constructors

Answer 2

1. built in

2. custom

Question 3

It’s a convention to ____________ of constructors to distinguish them from regular functions

Answer 3

capitalize the name

Question 4

function Book() { 
  // unfinished code
} 

var myBook = new Book();

myBook instanceof Book //

Answer 4

true

Question 5

function Book() { 
    // unfinished code
  } 

var myBook = new Book();

alert(myBook.constructor !== Book);

Answer 5

false

constructor points to Book

Question 6

var s = new String("text");
s.constructor === String;      // 
"text".constructor === String; //

Answer 6

true

true

Question 7

var a = new Array();
a.constructor === Array;       // true

[].__________ === Array; // true

Answer 7

constructor

Question 8

Although the constructor property can be used to check the type of an instance, it is generally recommended to only use the instanceof operator for this purpose

TRUE / FALSE

Answer 8

TRUE

Question 9

to check the type of an instance use instanceof or constuctor

WHY?

Answer 9

instanceOf

because the constructor property might be overwritten. As a result it’s not a reliable method for checking the type of an instance.

Question 10

A getter is expected to___________, while a setter receives the value being assigned to the property as an argument.

Answer 10

return a value

Question 11

The JavaScript language has _______ built-in constructors

Answer 11

9

Object(), 
Array(), 
String(), 
Number(), 
Boolean(), 
Date(), 
Function(), 
Error()
RegExp()

Question 12

Object literal notations are preferred to constructors

TRUE / FALSE

Answer 12

TRUE

Question 13

It’s important to remember to use the new keyword before all constructors. If you accidentally forget new, you will _______

Answer 13

be modifying the global object instead of the newly created object

Question 14

vehicle; // {}

var FuzzyBear = function FuzzyBear() { };
vehicle.constructor = FuzzyBear;

vehicle; // { constructor: function FuzzyBear() }
vehicle.constructor == FuzzyBear; //
vehicle instanceof FuzzyBear //
vehicle instanceof Vehicle //

Answer 14

true
false
true