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10 Mind-Blowing JavaScript Tricks Every Developer Should Know

Mene.tech on July 09, 2025

JavaScript is an incredibly versatile and powerful programming language that continues to evolve and amaze developers with its capabilities. Whethe...

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Massimo Artizzu • Jul 11

These "tricks" all marked as "1." are actually basic JavaScript syntax that's been available for years, except the one about DRY that has actually nothing to do with duplicated code.

AI slop is slop.

Mene.tech • Jul 11

Totally fair. These aren’t some deep hacks, just basic JavaScript stuff that a lot of us (me included) forget or overlook when we’re learning. And yeah, DRY isn’t just about using map, but things like that help reduce the same repetitive loop logic everywhere.
I actually wrote this draft in 2023 and just posted it without thinking much of it. Didn’t expect it to get more than 50 views, but here we are.

But hey, if it’s AI slop, at least the slop’s got reach

Mene.tech • Jul 11 • Edited

I’ve also corrected the numbering, honestly something I overlooked. Maybe my headline was a little overboard too
And just to say, I’m a big supporter of AI, but calling my post "AI slop" is a stretch. Maybe go with more constructive criticism next time?

You said the code has nothing to do with DRY, but I’d disagree. The whole point of DRY (Don't Repeat Yourself) is to avoid writing the same logic over and over and that includes patterns like looping and pushing inside arrays manually. Using map, filter, or reduce helps encapsulate that logic in a cleaner, reusable way.

// Repetitive pattern const squaredNumbers = []; for (let i = 0; i < numbers.length; i++) { squaredNumbers.push(numbers[i] ** 2); } // DRY version const squaredNumbers = numbers.map(num => num ** 2);

It’s literally the same result, but the second approach is less code, less repetition, and more readable. That’s a textbook DRY improvement not just about copy-pasting blocks, but reducing repeated patterns.

Not saying it's revolutionary, but to say it has "nothing" to do with DRY feels like a reach.

Eric Cornwell • Jul 15

I think there's room for semantic disagreement there. But to me this is more an example of imperative vs. declarative implementations.

Mene.tech • Jul 15

That’s fair. It’s definitely more declarative than imperative. But I’d still argue it touches DRY too, since you’re reducing repeated logic patterns. Maybe it sits in both worlds. Appreciate the perspective though!

Abdulbasit Alabi • Jul 15

const watched = new Proxy({}, { get(target, prop) { console.log(`Accessing ${prop}`); return target[prop]; }, set(target, prop, value) { console.log(`Setting ${prop} = ${value}`); target[prop] = value; return true; } }); watched.name = 'Basit'; // Logs: Setting name = Basit

Mene.tech • Jul 15

This is clean. I love how you used Proxy to log property access and updates. Super handy for debugging or even building out simple reactivity. Appreciate you dropping this here.

leob • Jul 11

LOL "mind blowing tricks" - all of this is just elementary ES6 basics ... and what's with the "numbering"? If you're not able or willing to get the numbering right, then maybe stick with unnumbered bullet points ;-)

Mene.tech • Jul 11

Thank you for your input🙂🙏

Abdulbasit Alabi • Jul 15

Array.prototype.last = function () { return this[this.length - 1]; }; [1, 2, 3].last(); // this would give 3

This patching built-ins

Mene.tech • Jul 15

I like this , makes the code feel way cleaner. I’m usually a bit cautious with patching built-ins, but for quick scripts or personal projects, this hits. Thank you so much for your inputs means a lot🙏

Abdulbasit Alabi • Jul 15

Really?