Understand Own Properties what's the point of hasOwnProperty

JavaScript
1

Tell us what’s happening:
Hi, I don’t understand what is the point of “hasOwnProperty” in this challenge
for (let x in canary) ownProps.push(x) - this code passed the challenge, and I’m lost about what exactly “hasOwnProperty” adds to the code in this situation

For me it seems like we use for…in loop to loop through properties of the object, then we are supposed to check if these properties exist with “hasOwnProperty”, and then add them to new array, which doesn’t make sense?

Your code so far


function Bird(name) {
this.name = name;
this.numLegs = 2;
}

let canary = new Bird("Tweety");
let ownProps = [];
// Only change code below this line
for (let x in canary) ownProps.push(x)

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Challenge: Understand Own Properties

Link to the challenge:

2

Hello @damians !

I believe you’ll understand the purpose of this in future lessons. Objects can have own properties, but also they can have properties that declared in their prototypes. Prototypes are covered in future lessons. Happy coding!

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