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Javascript in a Ninja Way

Deepan on October 18, 2019

Hi Dev, Today I'm gonna share my 7 favorite Javascript shorthand tips that will look cool and clean on your code. Alright, Let's begin. ...

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SavagePixie • Oct 18 '19

The equivalent long hand expression will be
if (myValue === true)

Wouldn't the equivalent longhand expression be if (myValue == true)? Your example will return false unless myValue is a boolean.

Other than that, all those are great features of JavaScript.

Blake Mealey • Oct 19 '19

Came to the comments to say this 😃

Patrick • Oct 18 '19

Yea I agree, that part is very misleading... its equiv to if (Boolean(myValue)) {...}

Deepan • Oct 20 '19 • Edited

Yeah, you are right. I'll change it right away. Thanks, patrik, Blake

Deepan • Oct 18 '19

I assumed that it's a boolean. I was just trying to explain the truthy expressions.
I'll put appropriate comments. Thanks for the feedback.

SavagePixie • Oct 18 '19

Oh, gotcha! I assumed you were checking that it was a truthy value.

Michael Laufer • Oct 18 '19

I would never use "2) Decimal Values with trailing zeroes" and would strongly advise against using this in anything other than personal projects. The only benefit you get is confusing other developers, especially juniors.

Deepan • Oct 20 '19

I think that up to one's perspective. We can easily see those expressions in mathematics.

Sam Holmes • Oct 22 '19 • Edited

Cool trick for #5. You could even include parameters for require like so:

required = (f, p) => {
  throw new Error(`Parameter ${p} for ${f} required.`);
}

foo = (bar = required('foo', 'bar')) => {
  return bar;
}

Eugene Karataev • Oct 20 '19

Nice list.
In the last example I prefer to use [1,2,3].includes(1) instead of ~[1,2,3].indexOf(1)

Juan F Gonzalez • Oct 20 '19

Wow, guess I became a ninja and didn't even realize it... 6 out of 7 tricks. Not bad

jacobdo • Oct 18 '19

Mandatory parameter seems very useful

Ryan Walker • Oct 20 '19

const num1 = +"100" Does this shorthand work in all browsers?

Deepan • Oct 20 '19

It's just usage of a unary operator '+'. So, I believe it will work the same on all browsers. But you cannot use const, instead of const use var since const is introduced in ES6.

Sam Holmes • Oct 22 '19 • Edited

I think #6 is code smell (bad advice). Instead be concise and use parseInt, parseFloat, or Number for typecasting

Sam Holmes • Oct 22 '19 • Edited

For #7 we could just use Array.prototype.includes() (developer.mozilla.org/en-US/docs/W...)

Varun • Oct 23 '19

I like the Mandatory Parameter way of throwing error for required fields.Its cool and enhances readability.
Thanks for sharing

Papidev • Oct 21 '19

Uhm nice to know , but points 5,6 and 7 seem less readable to me. Personally I prefer longhand in those cases.