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5 useful javascript tricks for begginers.

Minhazur Rahman Ratul on February 20, 2021

In this post, I will show you 5 awesome javascript tricks which will make your life more easier. And will help you to become a better developer. So...
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danim47c profile image
Daniel Mateos •

I think the best way you can obtain the most lengthy string in an array is this:

const mostLengthy = someArray
    .reduce((acc, i) =>
        i.length > acc.length
             ? i
             : acc
)
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Coderslang: Become a Software Engineer •

That's a good one, although it might be useful to first filter out nulls and undefineds from the array:

const mostLengthy = someArray
    .filter(item => item)
    .reduce((acc, i) => i.length > acc.length ? i : acc);
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Matthieu • • Edited

You can also do this way I believe (sort by the length of the words in descending order, then pick the first one).

const mostLengthy = someArray.sort((x, y) => y.length - x.length)[0]
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Maybe it's more understandable ? But I agree reduce is great :).

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Minhazur Rahman Ratul •

useful :)

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Benoît Schiex • • Edited

last_Item = arr.slice(-1) would not return the last item but a new array containing the last item.

you can do :

const lastItem = arr[arr.length-1]
const lastItem = arr.slice(-1)[0]
const lastItem = arr.slice(-1).pop()
const [lastItem] = arr.slice(-1)
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Minhazur Rahman Ratul •

wow nice. !

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Jon Randy 🎖️ • 
const last_item = array.reverse()[0]
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Kelly •

that one mutates the array, though

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Jon Randy 🎖️ •

Yeah. I always wondered why they decided to make it like that

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Juncheng • • Edited

Try with this:

const number = 23.6565
console.log(~~number);
const string = "24"
console.log(+24)
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nibelune profile image
Benoît Schiex •

This is a bitwise or.
Since bitwise operations only make sense on integers, the decimal part is truncated.

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CaptainOfPhB •

I think those are basic skills of javascript developer(maybe you are a new bee), and the second trick is not recommended, Math.round/Math.floor/Math.ceil are better choice, which will make your code more readable.

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Aspiiire •

That is really useful, thank you 😁

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baikai223 profile image
baikai223 •

获取数组的最后一项数据使用数组的api方法不是更好吗?arr.pop()

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Minhazur Rahman Ratul •

I don't understand what you have said :|

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baikai223 profile image
baikai223 •

Wouldn't it be better to use pop() instead of slice()?

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Minhazur Rahman Ratul •

you can use what ever you want. ......I know how to do that with slice so I have shown with slice. If you know how to do that with pop() you can use pop. :)

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Deepansh Dash •

Thanks it is useful.

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Ian Wijma •

Not 100% sure you should the weird int casting. Not everyone knows about it. And could cause confusion when reading it. Maybe just use parseInt. 😁 Really Cool post though!!

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Kamal Hossain •

thanks for sharing.

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Fábio Luciano •

By normal number, did you mean integers?

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Devendra Gaud •

I'm still wondering how the logic works in Trick-2.

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Minhazur Rahman Ratul •

Small trick ;)

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Devendra Gaud •

Ok, I just discovered two other ways similar to that trick.

console.log(~~5.95) 
console.log(5.95 >> 0)
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And I'm more confused now.

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developeratul profile image
Minhazur Rahman Ratul •

you can use what ever you want. Both of the tricks does the same thing. Or you can also use Math.floor() or Math.round()

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suvel rathneswar⚛️ •

Helpful ☺️

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