JavaScript Function Declarations vs Expressions Explained

The fastest JS code I wrote this year… wasn’t JavaScript. Today I published the deeper story. It starts with a simple problem: pure JavaScript was becoming the bottleneck for large image comparisons. I experimented with multiple approaches and benchmarks and eventually ported the core algorithm to Rust. Along the way, I looked at existing tools like odiff. It's very fast, but typically used through spawned processes or long-running helpers to avoid that overhead. The interesting part for me was the interface layer. Instead of spawning binaries or running a server, the library uses N-API to let Node call the Rust implementation directly. That removes the process overhead and makes batch diffing much cheaper. If you like performance deep dives, the full write-up is here: https://lnkd.in/dDP58i6q Also, thanks to HackerNoon for selecting it as a Top Story.

🚀 Day 37 - Revision Day 🔁 Today was all about revisiting previously learned JavaScript concepts and strengthening my foundation. No new topics......just focused revision to deepen understanding. 📚 What I revised: • JavaScript fundamentals (variables, data types) • Functions & scope • Arrays and objects • DOM basics • Problem-solving exercises ✅ Key Takeaways: ✔ Revision makes concepts stick better ✔ Small gaps become visible when you revisit ✔ Strong fundamentals = better coding confidence Slowing down today to move faster tomorrow...!💡 #LearnInPublic #JavaScript #WebDevelopment #CodingJourney #Consistency

𝗧𝗶𝗽𝘀 𝗙𝗼𝗿 𝗖𝗹𝗲𝗮𝗻 𝗝𝗮𝗩𝗮𝗦𝗰𝗿𝗶𝗽𝘁 𝗖𝗼𝗱𝗲 You want your JavaScript code to be clean and easy to read. Object destructuring helps you do this. It lets you extract object properties into variables in one line. Here's how it works: - Take properties from an object - Create variables with the same names You can set default values if a property does not exist. You can also rename variables if needed. Object destructuring is useful for: - Extracting nested values - Simplifying function parameters - Preventing undefined values - Making your code shorter and cleaner You can use object destructuring to: - Extract properties in one line - Set default values - Rename variables - Simplify function parameters Source: https://lnkd.in/gYEvMh5H

Ever felt confused about how reduce() actually works in JavaScript? 🤯 Where did the accumulator come from? Why does it sometimes start with 0? Why does the loop start from index 1 sometimes? The moment I finally understood it, everything clicked. If you've ever been confused about reduce(), my latest blog might help you. 👇 🔗 https://lnkd.in/g4hAcPyG #webdev #array-methods #reduce Hitesh Choudhary Piyush Garg Akash Kadlag Jay Kadlag

Revisiting Advanced JavaScript Fundamentals Today I spent some time revising a few important JavaScript concepts that every developer should master: ✅ Functions – the core building block of JavaScript ✅ Closures – understanding how functions remember their lexical scope ✅ Objects – structuring and organizing data effectively ✅ Object Destructuring – extracting values cleanly from objects ✅ Array Destructuring – writing cleaner and more readable code Sometimes the best way to improve as a developer is simply revisiting the fundamentals. Every time I review these concepts, I notice patterns and details I missed before.

🚨 Confused between the Spread (...) and Rest (...) operator in JavaScript? Many developers mix them up. 💡 They share the same syntax but serve completely different purposes depending on where they’re used. 🔹 Spread Operator • Expands elements from arrays or objects • Commonly used for copying, merging, or passing values • Helps maintain immutability in modern JavaScript • Makes code cleaner and easier to read 🔹 Rest Operator • Collects multiple values into a single array • Mostly used in function parameters or destructuring • Useful when working with an unknown number of arguments • Helps manage flexible and dynamic data ⚡ Quick rule many developers follow: • Spread → Expands values • Rest → Collects values 📌 Same syntax. Two powerful JavaScript features. #JavaScript #WebDevelopment #FrontendDevelopment #Coding #LearnToCode #100DaysOfCode

🚀 Day 82 of My #100DaysOfCode Challenge Today I learned about a very useful JavaScript feature — Optional Chaining ("?."). When working with deeply nested objects, accessing properties can sometimes cause errors if a value is "undefined" or "null". Optional chaining helps solve this problem by allowing us to safely access nested properties without breaking the code. Example without Optional Chaining const user = { profile: { name: "Tejal" } }; console.log(user.profile.name); If "profile" doesn’t exist, this code would throw an error. Example with Optional Chaining const user = { profile: { name: "Tejal" } }; console.log(user?.profile?.name); Output Tejal If a property doesn't exist, JavaScript simply returns undefined instead of throwing an error. Why this is useful • Prevents runtime errors • Makes code cleaner and shorter • Helpful when working with APIs and complex objects Small modern features like this make JavaScript development much smoother. Continuing to explore deeper concepts and improving step by step. 💻✨ #Day82 #100DaysOfCode #JavaScript #OptionalChaining #WebDevelopment #LearningInPublic

📣 𝗡𝗲𝘅𝘁 𝗕𝗹𝗼𝗴 𝗶𝘀 𝗛𝗲𝗿𝗲! ⤵️ Arrow Functions in JavaScript — A Simpler Way to Write Functions ⚡🧠 Regular functions work fine. But when logic becomes small and frequent, typing all that syntax starts feeling heavy. This blog explains arrow functions in a clear, beginner-friendly way — focusing on syntax, mental models, and real usage. 🔗 𝗥𝗲𝗮𝗱 𝗵𝗲𝗿𝗲: https://lnkd.in/gMBAZxX5 𝗧𝗼𝗽𝗶𝗰𝘀 𝗰𝗼𝘃𝗲𝗿𝗲𝗱 ✍🏻: ⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺⎺ ⇢ What arrow functions actually are ⇢ Converting normal functions to arrow step by step ⇢ Basic syntax and parameter rules ⇢ Implicit return — the real magic ⇢ When implicit return does NOT work ⇢ Using arrow functions in map(), filter(), and callbacks ⇢ Common beginner mistakes and how to fix them ⇢ When to use arrow functions vs regular functions ⇢ Practical examples for faster understanding 💬 If functions still feel verbose or repetitive, this article helps you write cleaner and more modern JavaScript. #ChaiAurCode #JavaScript #ArrowFunctions #WebDevelopment #ProgrammingBasics #Beginners #LearningInPublic #100DaysOfCoding

If you misunderstand `𝐯𝐚𝐫`, `𝐥𝐞𝐭`, 𝐚𝐧𝐝 `𝐜𝐨𝐧𝐬𝐭`, your bugs will multiply quietly. Master these three, and your JavaScript becomes predictable. I like to explain them with simple mental models. `𝐯𝐚𝐫` is like a basic box. You can put something in it, replace it, and even access it outside the block where it was created. It’s flexible—but that flexibility often creates confusion due to function scope and re-declarations. `𝐥𝐞𝐭` is a box with a protective boundary. You can change what’s inside, but only within its block scope. Step outside that boundary, and it no longer exists. This makes your code safer and more controlled. `𝐜𝐨𝐧𝐬𝐭` is a locked cage. You cannot reassign it to something else. However, if it holds an object or array, the contents can still change—because the reference is locked, not the internal data. Understanding this difference prevents scope leaks, accidental overwrites, and unpredictable behavior. Here’s a practical rule: * Use `𝐜𝐨𝐧𝐬𝐭` by default * Use `𝐥𝐞𝐭` when reassignment is necessary * Avoid `𝐯𝐚𝐫` in modern JavaScript Clean code starts with disciplined variable declarations. When reviewing your code, are you choosing the right “box” intentionally—or out of habit? #JavaScript #FrontendDevelopment #WebEngineering #CleanCode #ProgrammingFundamentals #SoftwareEngineering #CodeQuality

𝐂𝐚𝐥𝐥𝐛𝐚𝐜𝐤𝐬 𝐚𝐫𝐞 𝐭𝐡𝐞 𝐫𝐞𝐚𝐬𝐨𝐧 𝐉𝐚𝐯𝐚𝐒𝐜𝐫𝐢𝐩𝐭 𝐜𝐚𝐧 𝐛𝐞𝐡𝐚𝐯𝐞 𝐚𝐬𝐲𝐧𝐜𝐡𝐫𝐨𝐧𝐨𝐮𝐬𝐥𝐲 𝐝𝐞𝐬𝐩𝐢𝐭𝐞 𝐛𝐞𝐢𝐧𝐠 𝐬𝐢𝐧𝐠𝐥𝐞-𝐭𝐡𝐫𝐞𝐚𝐝𝐞𝐝. While revisiting some fundamentals today, I explored how 𝐜𝐚𝐥𝐥𝐛𝐚𝐜𝐤 𝐟𝐮𝐧𝐜𝐭𝐢𝐨𝐧𝐬 help JavaScript handle operations that would otherwise block execution. A callback function is simply a function passed as an argument to another function so that it can be executed later. This becomes important because JavaScript is 𝐬𝐲𝐧𝐜𝐡𝐫𝐨𝐧𝐨𝐮𝐬 and 𝐬𝐢𝐧𝐠𝐥𝐞-𝐭𝐡𝐫𝐞𝐚𝐝𝐞𝐝. It has a single 𝐜𝐚𝐥𝐥 𝐬𝐭𝐚𝐜𝐤, often referred to as the 𝐦𝐚𝐢𝐧 𝐭𝐡𝐫𝐞𝐚𝐝, where every piece of code on a page gets executed. If a long or heavy operation runs on this thread, it 𝐛𝐥𝐨𝐜𝐤𝐬 𝐭𝐡𝐞 𝐜𝐚𝐥𝐥 𝐬𝐭𝐚𝐜𝐤, meaning nothing else can execute until it finishes. That’s why asynchronous patterns exist. What clarified this for me: • 𝐂𝐚𝐥𝐥𝐛𝐚𝐜𝐤𝐬 𝐞𝐧𝐚𝐛𝐥𝐞 𝐚𝐬𝐲𝐧𝐜𝐡𝐫𝐨𝐧𝐨𝐮𝐬 𝐛𝐞𝐡𝐚𝐯𝐢𝐨𝐫 • APIs like 𝐬𝐞𝐭𝐓𝐢𝐦𝐞𝐨𝐮𝐭 allow tasks to run later • Heavy operations should never 𝐛𝐥𝐨𝐜𝐤 𝐭𝐡𝐞 𝐦𝐚𝐢𝐧 𝐭𝐡𝐫𝐞𝐚𝐝 • The call stack must remain free for smooth execution Another interesting detail is how 𝐞𝐯𝐞𝐧𝐭 𝐥𝐢𝐬𝐭𝐞𝐧𝐞𝐫𝐬 interact with memory. Every time an 𝐞𝐯𝐞𝐧𝐭 𝐥𝐢𝐬𝐭𝐞𝐧𝐞𝐫 is attached, it creates a 𝐜𝐥𝐨𝐬𝐮𝐫𝐞, which means it holds references to variables from its surrounding scope. Because of that, event listeners can consume memory if they are not managed properly. For example, attaching hundreds of event listeners (like onclick handlers for many buttons) can slow a page down because each listener holds its own closure and scope. Removing unused listeners allows 𝐠𝐚𝐫𝐛𝐚𝐠𝐞 𝐜𝐨𝐥𝐥𝐞𝐜𝐭𝐢𝐨𝐧 to reclaim that memory. Understanding this made me appreciate how callbacks, closures, and memory management are all connected in JavaScript. #JavaScript #SoftwareEngineering #DeveloperJourney #LearningInPublic #Programming #TechCommunity #WebDevelopment