HARD JavaScript Challenges | Do You REALLY Know JS?

Do you actually know the intricate details of JavaScript? Or do you just have enough surface knowledge to know the basics? See how many of this tough challenges you can solve!

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Timestamps:
0:00 How Well Do You Know JavaScript?
0:19 This Madness
1:09 Arrays Can Do What?
2:00 Adding... Strings?
2:28 Duplicate Variables
3:31 Splicing Arrays
4:22 setTimeout Is Broken?
5:40 The Comma Operator
6:20 Equality Is Not Equal
7:25 Invalid Object Property Names?
8:12 Asynchronous Promise Chaining
9:54 Up Next

[woodylucas]

0:40 Everything you said is correct; I just wanted to show how we can implement this approach. We can bind the function by using bind(). Since we want to reuse the function later and have a reference to it, we can use bind() as follows: const getName = obj.getName.bind(obj). Then, line 8 will work correctly.

[bikidas]

0:40 golden rule to remeber with this is where it was called from no mattter what the trajectory was, the call site matters in almost nearly all of the cases since in getName we are just storing the reference of the method it was actually called by getName which is defined in the global scope and thus undefined

[AnnaKladovaBohun]

Very usefull. Thanks for your great content, Conner!

[DpakSharmaNoida]

Love it, bring more of this.
I was able to do most of them

[Tony.Nguyen]

My favourite JS youtuber, I always learn something from you vids.

[irfanmohammad]

For first challenge if you run this code in browser it will give you empty string and if you run that in codepen it will give you codepen and if you run that on in stackblitz it will throw error

[ZeZeko]

4:22 throw in promises into the mix for a good measure

[anup-kaushal]

I’m learning JS and I completed the first four challenges without any trouble. The next challenge is about array methods, which I’m not yet familiar with, so I’ll learn about them before proceeding with this video. I’ll come back to this video later. I really appreciate you for making this video because it makes learning much easier. I’ll subscribe for more great content like this.

[riacharda]

Damn, i definitely learnt something new today. I got hung up on the object and promise ones.

[sudheervajrapu]

Love your video. they're straight to the point. Keep doing more videos like this..

[abdulrafaykhan]

i have learned comma operator, invalid object property name and duplicating variables, thanks

[mohamedelmahdy]

Actually learning from you alot dude you truly JavaScript Sensi 🧑‍🏫🧑‍🏫

[typescriptuser]

I didn’t know JavaScript was this complicated until I see your contents. They’re really helpful! Thank you. :)

[soniablanche]

the only one I didn't know was the one that looked like a tuple

[shyt]

6:56 seem that the most confusing thing in js pass by value and pass by reference

[oualidel-feraoui]

Yes i want to see more of these. You're a great content creator

[asagiai]

I think it is more confusing rather than hard.

My answers before I see the actual output.

2:33 I think this is called closure.
Out
2
1

3:32
Out
[1, 2, one, two, 4, 5]

4:24 even though it is 0 sec.
Out
1
3
2

5:41 ok, I haven't seen a comma operator inside a parentheses before. That is not a function. So .idk.

6:24 This is not how you check for deep equality in JS.
Out
False
False

7:26 This can work, but this is not the syntax.
Out
Error?

8:14  Hmm, not sure, but

Out
5
10
20

The question now is, do you really care about what I or what someone else did?

[eshw]

I think code challenges or more interview prep for js and react for the 2023 market would be great, in terms of what to expect now. Great content.

[mahmoudalaskalany]

Man, i got JS knowledge in these 10 mins more than my whole 4 years of college 🔥🔥

[davesharma]

I actually got most of them right
Guess im getting strong in js😊