...spread operator and rest operator - Beau teaches JavaScript

The spread operator (...) spreads out the elements of an array (or iterable object). The rest operator condenses elements. The spread and rest operators are great additions to ES6!
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[@abraaoazevedo5077]

"use your code for good" - loved it

[@milleniummoses]

Thank you. These aren't well explained as I was going through the exercises on the website. I came here looking for better understanding.I get them now. Very useful.

[@pra__bhu]

Totally agree to you man :D..
Makes much more sense in the video

[@SanthanamSridharan]

Same!

[@azizmejri4850]

totally agree ! they didn'te xplain how to copy the array, they just said "const spreaded = ...arr; // will throw a syntax error" which confuse the hell out of u

[@leeallen2521]

Yep, they said they would go through spread & rest operators in detail later (under basic JS) but they didnt. So glad Im not the only one :)

[@kelvinmwendwa]

Haha. Same

[@panthonyy]

I just found the series "Beau teaches JavaScript," and boy, this is the best JavaScript tutorial series (at least about the topics covered). He is straight to the point, has a clear and clean voice that is easy to understand, and uses a good speech pace. Well, anyway, You got a new sub with notifications on ;)

[@andreagirardi833]

Thank you. The FCC exercise had poor explanation and the concept here is well expanded and is clear. Thumbs up!

[@justaprogrammer3764]

i find the real only curriculum is very confusing at times and speed up. This did also help me.

[@Makebuildmodify]

Why is this video not embedded in the ES6 "rest" and "spread" pages!!??

[@oufcena5092]

Get a hint will get you here ;3

[@EminoMeneko]

I love this.
Clear, not excessively long, right to the point.

[@sourandbitter3062]

Love your voice and your straightforward explanations Beau. Very good tutorials.

[@pavXX]

Thanks for the explanation. The FCC exercise explanation sucked.

[@Nyah420]

Harsh but accurate.

[@richardl802]

Great - thanks for your help in understanding this. Useful to see the different use cases explained together.

[@Ninethepoet]

Thank you thanks you thank you. I was stuck after getting about 50% progress and I needed to redo the whole course because my fundamentals were wrong.

[@herolivesnu]

Wow! You did a great job here in your explanations. I can't just pass without saying "God will continue to bless you with more knowledge".

[@deepeshsingh923]

Straight forward and useful explanation. Pretty helpful.

[@rnmatsuda]

This is extremely helpful and well explained. Thank you, Beau!

[@mohd0606]

Thanks, man a quick and concise video. Now the concept was clear. Kudos to you. :)

[@SanthanamSridharan]

Thank you! This is superb addition to the website tutorial!

[@amwostan6505]

Thanks Beau. I was stuck on the FCC lesson about REST parameters and this really explained it well.

[@Amine-wp6de]

Thanks for the clear and precise explanation of the 3 dots !

[@deaddoomed2380]

so simple, so useful and so badly explained. this video made it much more clear for me, thanks!

[@bran8370]

Great! You explained this well and made it easy to understand. I loved all the examples--really nailed it down for me. Thanks~

[@milanm9907]

Crystal clear, thank you Beau!

[@MatthewChenIsAwesome]

also a nice tip with spread operator: if you're using react, instead of passing props like:
```
render() {
const {key, title, summary, imageURL} = this.state;
return (
//some stuff
//other stuff
}
```
you can do:
```
render() {
const {...myComponentProps} = this.state;
return (
//some stuff
//other stuff
}
```

[@oufcena5092]

I still haven't finished JS yet so, maybe I'll get it later. thx tho ;3

[@ahmad-ali14]

this is the best explain for those methods. many thanks.

[@user-cool839]

Beau, you are the best! Thank you!👍👍👍

[@grandpowr]

Legit the best Javascript teaching series in youtube!

[@adarshtiwari7395]

Concise and to the poin! Thanks a ton

[@d0m2288]

Concise and informative. Much appreciated.

[@braulioandre2918]

When passing elements of an array as arguments to a function, we can also use destructuring assignment:
function ( [x, y, z] ). In this case when we call the function we don't need to use the spread operator...

[@buddha0004]

Thanks...I'm in the middle of these exercises for the FCC javascript cert now; Sometimes the directions aren't clear to me or confusing...(visual learner, I guess).

[@phillipscards]

Thanks for such a great explanation. Helped me make some sense of it.

[@vijaykumarreddyalavala3713]

Thank you so much for this video. Short and well explained

[@alexlions8633]

thanks )) you are one of the best teaacher in js in the world

[@DerekPK]

const sum = (x, y, z) => {
const args = [x, y, z];
return args.reduce((a, b) => a + b, 0);
}

[@CameronPak]

Now I know how to spread... Woo!

[@devjeff3192]

Beau is awesome teacher !!! But I couldn't find any video tutorials regarding to ES6 on freeCodeCamp ! But finally found 'em on RUclips ! :)

[@atifworld]

so easily explained, thank you

[@yufeizhan726]

So good. Highly recommended!

[@khajahussainpathan1064]

Thank you, Very good explanation. Understood clearly about Spread and rest Operator

[@asfandiyar5829]

Awesome! Exactly what I was looking for. Clear explanation. Thanks

[@bk-entertainz7081]

Wow! You made this so simple. THANK YOU!!!

[@00733adnan]

Awesome. Simple and meaningful.

[@ahmed_raaphat]

Don't forget to subscribe and remember, USE YOUR CODE FOR GOOD!
Thanks for the great explanation.

[@Akephalos204]

clear as crystal, thanks

[@andrewtcoder]

Thank you for this video!!!

[@aceborja1656]

Thank you. Very useful explanation. Great job Beau!

[@rahulgupta6892]

Actually if we pass the extra arguments to the function it is not ignored by the function, rather it will accept those arguments as additional arguments, such function with additional arguments are known as "Varargs".

[@kenbinta2246]

Well Explained. I did not have to watch the video twice to understand

[@oufcena5092]

...Spread operator allows an array to get more elements.
arr1.concat(arr2) == [...arr1, ...arr2]; //you can add more elements unlike .concat() function
...Rest operator allows a function to get more arguments.
var multiply = (multiplier, ...args) => args.map( (element) => multiplier * element );
console.log(multiply(2, 1, 2, 3));
() means function
=> means return
map() method creates a new array with the results of calling a function for every array element.

[@girlandhercomputer7204]

Thank you, your explanation is very clear and to the point!

[@miaprivate9742]

It was an awesome explanation for rest of my life

[@stackdevlopr]

explained beautifully!

[@DelicatelyStunning]

Thank you for this video. I spent way too long trying to decipher the documentation at MDN.

[@daniamsalem]

Very simple explanation, thank you very much

[@MrWardo2009]

Thank you for doing these videos! Really helped me !

[@teenytinytoons]

Beau is my hero!

[@DColls2488]

GREAT VIDEO FOR ROOKIE CODERS 🙏

[@vladislavbarbarii2089]

Just excellent explanation.Thank you

[@lackadaisicallass9041]

Very interesting! Can't wait to use it. Thank you!

[@jt.633]

great explanation thank you! although the last one about the rest operator is still confusing

[@soygeekgirl]

Genial , super bien explicado!! ..

[@pepsivanilla93]

Great explanation thanks so much

[@nebojsapavlovic8031]

Thanks Beau! This I understand.

[@kodave]

Again, thanks for the succinct explanation

[@user-kn4oi9oh4i]

Thank you for this Bo

[@Zakyrie]

Really nice. I'll be using your videos as a reference point.

[@WeirdStuffaaaa]

I am on my 3rd year of IT degree . I got to know this today

[@chengjinfei8139]

in this section we talked about spread out arrays. here's another helpful link for spread object. ruclips.net/video/MpnzQozwLGI/видео.html

[@diegoavendanohernandez9908]

Thank you much, super clear

[@justincook8473]

What will happen if you have nested arrays? For example, [[1,2], ["three", "four"]]

[@oufcena5092]

//return []
try yourself in dev tools JS console
var multiply = (multiplier, ...args) => args.map( (element) => multiplier * element );
console.log(multiply([[1,2], ["three", "four"]]));

[@deathknell1970]

u are a great teacher

[@BneiAnusim]

They should add this video to FreeCodeCamp because they have watered down the explanation on "Use the Rest Parameter with Function Parameters".

[@laser1915]

spread operator also prevents state mutation

[@GeorgeEmad]

clear and simple and to the point amazing

[@ih4722]

Simple yet powerful.

[@iVuDang]

Thank you, very helpful!

[@santhoshnatarajan5271]

Thank you for the clear explanation

[@israeli_soldier]

Excellent video

[@brootalbap]

Man the ES6 lessons are all so awfully bad explained on fcc :( Thanks so much for the explanation that helped a bit :(

[@whathefuckisthis]

@@MasterofLightning totally, i thought i was going crazy. glad it's not just me

[@eledorusso]

the best tutorials

[@zeroxcrusher]

Thanks! ES6 course is so badly made, so this helps.

[@grantlineful]

Great explanation! Thank you.

[@eminm6383]

Great, clear explanation. Well done. 🙏 thnaks a lot

[@MohsinKhan-wv3ep]

Best video i have ever watched ❤

[@lalaithan]

Excellent presentation.

[@LuisMorales-yx8di]

Thanks, really helpful

[@JamesFrederickstech]

makes a little more sense but I'm still on shaky legs here. will keep working with these operators until the lightbulb goes off.

[@mackynyxz]

Nice explanation

[@Moorcheh]

VERY fluid explanation thanks FCC! Btw the excersizes' explanation needs a change!

[@stavroskefaleas6320]

Omg.This is awesome!

[@JavedBaloch786]

To convert string to array
let str = "Hello";
let x = [...str];

[@Shmack_]

Great tutorial thank you!

[@hyejungk.6234]

amazing tut! appreciate a bunch!

[@BlueIceAce2015]

Great explanation, thanks!

[@akagragupta9968]

well thank you so much , I was earlier just so confused now I am clear

[@igudy]

Thank you!

[@XodiyevAcademy]

Respeact very very clear is unsdrenstand

[@kevanhaggins6699]

beau, you're awesome.

[@SwietyPatryk]

It seems to be a mistake as arr1.concat(arr2) will return [0, 1, 2]. It should be arr1 = arr1.concat(arr2) to return [0, 1, 2, 3, 4, 5]

[@ohiwantyoutobelieve]

Excellent, ty

[@solaraproject3614]

Thank you

[@egbecharze2780]

You are too good.