Object Oriented Programming Constructor question

JavaScript
1

Tell us what’s happening:
This lessons doesn’t make much sense to me. We are asked to use the instance of instead of candidate.constructor === Dog in the tasks section in the console. But when I hit submit it says I still need to use the constructor? Isn’t the constructor candidate?

Wouldn’t candidate instanceof Dog be true automatically then?

Your code so far


function Dog(name) {
this.name = name;
}

// Only change code below this line


function joinDogFraternity(candidate) {
if(candidate instanceof Dog){
  return true; 
} else {
  return false; 
}
}

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.125 Safari/537.36.

Challenge: Understand the Constructor Property

Link to the challenge:

2

You are asked to use constructor. I’ll give you a similar example:

function Airplane(brand){
this.brand = brand
}
function Dog(name){
this.name = name
}
let myDog = new Dog("Joan")
let boeing = new Airplane("boeing")

function isItAnAirplane(object){
if(object.constructor=== Airplane){
return true
}
return false
}
let checkBoeing = isItAnAirplane(boeing)
let checkDog = isItAnAirplane(myDog)
console.log(checkBoeing,checkDog)

What I’d expect

  • paste that into the browser’s terminal
  • check the constructor property manually
  • See the output of the console log( Should be true false)

I don’t believe much in straight answers, and because you’re an avid learner I’m giving a bit complicated reply :slight_smile:

If you can connect the output true false with the inspection of the elements, then you’re on the safe side. Conclusion: the browser creates a constructor property on every instance of an object. But this can be overwritten.

3

Perfect! That makes sense. Thank you for not giving the answer away.

1 Like