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Cover image for What’s new in Javascript?

What’s new in Javascript?

Some of the new features are still proposal / not compatible in all browsers. So if you are playing with the code, try to use Google Chrome.
And some of them may

Private Fields

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From the counterDemo class, the #counter value is private. If we try to access the #counter, then syntax error will be shown.

Big Int Multiplication

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We can multiply 1234567890123456789n * 123n and obtain the correct value if we use BigInt.

Array Flat

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Array.flat will convert nested array items to a flat list. By default, it will convert 1 level deep. You can use

const array = [ 1, [2 , [3 , 4 , [5 , 6 ] ]]]
array.flat(Infinity);
The output will be 1 2 3 4 5 6. if we use Infinity it will recursively convert to a flat list.

Object.fromEntries

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We have use Object.entries in many cases. It will return an array from an object. Similarly, we can use the Object.fromEntries that will return the object from an array.

Top comments (10)

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genta profile image
Fabio Russo

Oh that Array.flat() is so tasty for me!

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ayudhkrgupta14 profile image
Ayudh Kumar Gupta

any possible usecases?

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genta profile image
Fabio Russo

Hm... using arr.flat().includes(something) to find into nested arrays without using recursion.
Dunno, just the first usecase jumped into my mind.

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qcgm1978 profile image
Youth

It works in chrome devtools now. I found Cannot mix BigInt and other types, use explicit conversions.
So don't omit the trailing n in each number.

1234567890123456789n * 123n
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rohovdmytro profile image
Rohov Dmytro • Edited on

Private Fields

What a crazy world we are living in.

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jillesvangurp profile image
Jilles van Gurp

I treat Javascript like a compilation target for more sane languages these days.

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tojacob profile image
Jacob Samuel G.

Great post!

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larsklopstra profile image
Lars Klopstra ⚑

I don't know why but my brain thinks your banner is written as JAASCRIPT πŸ˜‚

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pjijin profile image
Jijin P πŸ‘¨β€πŸ’»πŸ¦„ Author • Edited on

V is hidden there 😜 I have used ASCII text generator to do that 😊

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c0d3rm0nk3y profile image
Peter

Excellent Summary of what is coming in javascript. thank you

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