JS Infinite Currying Explained

🚀 Using `match()` Method of String Object (JavaScript) The `match()` method of a string object searches the string for a match against a regular expression. If the `g` flag is present, it returns an array of all matching substrings. If the `g` flag is absent, it returns the same type of array as `exec()`. If no match is found, it returns `null`. It's a versatile method for extracting matching substrings from a string. #JavaScript #WebDev #Frontend #JS #professional #career #development

🚀 **JavaScript Interview Question** What will be the output of this code? ```js const obj = { a: { b: 0 } }; const v1 = obj?.a?.b || 42; const v2 = obj?.a?.b ?? 42; console.log(v1, v2); ``` 🤔 **Think before you scroll...** --- #JavaScript #Frontend #WebDevelopment #CodingInterview #ReactJS

most developers don't know the difference between null , undefined and "" and it's breaking their React forms silently. - always initialise string state with ' ' not undefined - always initialise array state with [ ] not undefined - always initialise object state with { } not undefined here's why it matters beyond the warning: - undefined means "this was never set" - null means "this was intentionally set to nothing" - ' ' means "this exists but is currently empty" React treats these three things completely differently when rendering. your form works locally because you fill it in immediately. it breaks in production because someone submits without touching a field. initialise your state properly. #reactjs #typescript #webdevelopment #buildinpublic #javascript

🚀 Array Methods: splice and slice (JavaScript) The `splice()` method modifies an array by removing or replacing existing elements and/or adding new elements in place. It takes the starting index and the number of elements to remove as arguments, and optionally, new elements to insert. The `slice()` method returns a shallow copy of a portion of an array into a new array object selected from start to end (end not included) where start and end represent the index of items in that array. `slice()` does not modify the original array. #JavaScript #WebDev #Frontend #JS #professional #career #development

One interesting question I recently came across in a React interview: 👉 “If JavaScript already has getElementById(), why do we need useRef in React?” Here’s the understanding 👇 ✅ React uses a Virtual DOM, so direct DOM manipulation is discouraged. ✅ useRef provides a safe way to access DOM elements inside React components. ✅ Updating a ref does not trigger re-render, making it useful for storing mutable values. ✅ It keeps code component-scoped, cleaner, and React-friendly. 📌 Simple Answer: useRef lets us access DOM elements and persist values across renders without affecting the component lifecycle. #reactjs #hooks #useref #frontend

Many developers say hoisting moves code to the top of the file or block, but that is a myth. Hoisting does not actually move code. It is mainly about how the JavaScript engine allocates memory for variables and functions during the creation phase of execution contexts. #Hoisting #JS #JavaScript

What is a closure in JavaScript? A closure is a function that remembers variables from its outer scope even after that scope has finished executing. Why does this work? - `createCounter` runs once - It creates a variable `count` - The inner function “closes over” that variable - Even after `createCounter` finishes, `count` is still accessible Each time `counter()` runs: → it uses the same preserved state 💡 Closures are everywhere: - React hooks - Event handlers - Memoization - Encapsulation patterns They’re not just a concept — they’re part of how JavaScript manages state. #Frontend #JavaScript #React #WebDevelopment #SoftwareEngineering

Hey JavaScript devs 👋 Did you know `this` can silently disappear in 3 very common situations? 1. Detaching a method from its object const fn = obj.greet; fn(); // this → undefined 💀 2. Passing a method as a callback setTimeout(obj.greet, 0); // this → gone [1,2,3].forEach(obj.process); // same story 3. Arrow function in an object literal const obj = {  name: 'Pavel',  greet: () => console.log(this.name) // this → global, not obj }; The fix is always one of three things: `.bind()`, a wrapper arrow function, or class field arrow methods. Which one bit you the hardest? Drop it in the comments 👇 #JavaScript #WebDev #Frontend #JS

🧠 Day 20 of 21days challenge JavaScript "this" – Arrow vs Normal Function 🤯 Not all functions handle "this" the same way. Normal functions get "this" from how they are called. Arrow functions inherit "this" from their surrounding scope. For easy understanding :- Normal function → dynamic this Arrow function → lexical this Arrow does NOT have its own this 👉 That’s why arrow functions behave differently This changed how I use functions 🚀 #JavaScript #ThisKeyword #InterviewPrep #Frontend

🚀 Preventing Default Event Behavior with `preventDefault` (JavaScript) Many DOM events have default behaviors associated with them, such as submitting a form or following a link. You can prevent these default behaviors using the `preventDefault()` method of the event object. This is useful for overriding the default behavior and implementing custom logic. For example, you can prevent a form from submitting and instead validate the input fields using JavaScript. Use `preventDefault()` judiciously, as it can sometimes disrupt the expected user experience. #JavaScript #WebDev #Frontend #JS #professional #career #development