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Change your old methods for writing a JavaScript Code - Shorthand's for JavaScript Code

Simc Dev on August 04, 2022

1. Shorthand for if with multiple OR(||) conditions if (car === 'audi' || car === 'BMW' || car === 'Tesla') { //code } Ent...

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Anton B • Aug 4 '22

On 6th example i would rather use it in that way
type === 'heigth' ? height() : width()

it is more clear for me and for other i guess, and can be passed different arguments to functions

Mike Jacobson • Aug 7 '22

I agree. It also makes it easier to do a global search for all places where those functions are invoked.

Fen • Aug 4 '22

7th example can be written with ??. The difference is that values that evaluate to false would pass but if you use || they don't

Example:

false ?? 0 // false
false || 0 // 0

mikcat • Aug 6 '22

Be careful if you refactor switch by object, because switch uses strict uses strict comparison ===.

console.log(data['1']); will return 'Case one' but switch('1') will jump to the default branch.

Leonardo Montini • Aug 4 '22

The 7th example is not entirely correct though.

You replace

if(amount === null) {
    amount = 0;
}

with

console.log(amount || 0); //0

But if amount is undefined, it will not enter your if, but still undefined || 0 returns 0.

In short, you can't replace === null with the || operator as the behaviour is slightly different.

dmk1111 • Aug 6 '22

in suggested option console.log will still fire with undefined but with if case it won't fire;
works in this particular case. In case you have to return default value it won't work

Danny Engelman • Aug 6 '22

'Audi,BMW,Tesla,Daf,Volkswagen'.includes(car);

or even without ,

mustapha chatbi • Aug 8 '22

this would be a good trick if used just on typescript where car has to have enum type that allows only mentioned car brands
and here is why ( counter example on js )

Rishi U • Aug 7 '22

2nd Example optional chaining will return undefined if console.log like that, you would probably need to do use a ternary instead if you didn't want to print undefined.
but thanks for this.