Make it Short - Make it Better

Hey there Fellow Javascript Coder!
Whether you're a experienced programmer or just someone who just started with javascript basics, this list of hacks is definitely for you! Please note that you might have already known one or more features of javascript from the below list, and that's awesome! But not everyone knows them 😉

So let's straight hop in!

Convert Any Datatype to Boolean

By using !! in front of any variable, we can get the Boolean version of it! Let's see how:

let variable = 100;
variable = !!variable // returns true
variable = 0;
variable = !!variable //returns false

Isn't this easier to write and use in real life?
Well, this is more easier:

let variable = 100;
if(variable) console.log("True"); // Logs True!
variable = 0;
if(variable) console.log("True"); // doesn't log anything

Find whether a property exists in an Object

If you were using if(obj.property) or if(obj["property"]) till now, it's time to make your code more readable by using if("property" in obj).

Become Lazy and truncate Array just as you wanted

This just works!

let arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
console.log(arr); // Logs all the 10 elements
arr.length = 5;
console.log(arr); // Logs only [1, 2, 3, 4, 5] Holy Moly!?

Remove Duplicates from your Array

let arr = [1, 2, 1];
console.log(arr); // [1, 2, 1], as expected.
arr = Array.from(new Set(arr));
console.log(arr); // [1, 2], and cheers!

Avoid Server Lag during 2 or more Array Concats

Instead of using this:

let list1 = ['a', 'b', 'c', 'd', 'e'];
let list2 = ['f', 'g', 'h', 'i', 'j'];

let list = list1.concat(list2);

Try using this alternative:

let list1 = ['a', 'b', 'c', 'd', 'e'];
let list2 = ['f', 'g', 'h', 'i', 'j'];

let list = list1.push.apply(list1, list2)

The latter code saves your server from high memory consumption because the first code creates a new array in memory, whereas this one works with the list1 array instead of creating a new array.

I hope I made you learn something new today! If I did, consider hitting a like, a unicorn and a bookmark on this Post! Also you can hit a star on my current project - Reejs at https://github.com/rovelstars/reejs , a star means a lot to me!

Have a nice day 🙃!

P.S. Comment down below if you have any ideas on what the next blog should be, I will try my best if I can write on it!

Top comments (12)

thecodingcrow • Sep 11 '22

very much agree on the whole array part! unnoticed mutations can be such a pain in the ass!

Ren Hiyama • Sep 11 '22

Reminds me of GIGO - Garbage In Garbage Out 🙃

Tracy Gilmore • Sep 11 '22

Hi Ren, An alternative to if(variable) console.log("True"); can be found as a method in the Console API., although the logic needs to be inverted.

console.assert expects at least two parameters; a Boolean assertion and a message (or any other data) you want to present.

So the alternative to the above code is console.assert(!variable, "True"). It is typically used to flag up when something went wrong but I have never seen it used in production code.

Ren Hiyama • Sep 11 '22

You probably didnt see it in production code because many people know what assert does, including me! I just use console.log during testing and remove them when their logging work for testing is over

Al - Naucode • Sep 10 '22

Thanks, it was a good read, bookmarked, and followed!

Yuwang Cai • Sep 12 '22

if (obj.property) does not equal if (property in obj) when obj.property is falsy. And I really think arr.length should be considered immutable. Good point though!