Understanding call(), apply(), and bind() in JavaScript

I ran this JavaScript snippet, and the output completely surprised me 😳. Day 10: How JavaScript actually handles a async operations ⚙️. 🧠 Logic: 🔹 JS execution always starts with synchronous code -> so "start", "First" & "end" log first. 🔹 Inside the loop, setTimeout is added to macrotask queue (it will run later). 🔹 Promise.then() is added to microtask queue (these will run right after sync code), cause of high priority then macrotask queue. 🔹 Inside asyncFn(), when execution hits await it pauses that function exec & waits for promise to get resolve. 🔹 In the mean time, event Loop continue with promise callback in microTask, one it's completed, the promise get resolved in asyncFn() & then it prints ("Second") to console. 🔹 And the last, the setTimeout callback in macroTask queue gets executed. So:  ✅ Promise run first (microTasks). ⏱️ SetTimeout run after (macroTasks). That's why promise 0, promise 1, promise 2, and Second appear before all TimeOut logs. #Javascript #InterviewPrep  #100DaysOfCode #CodingChallenge  #JavaScript #CodingInterview #JSChallenges

✨Day 3/28 Consistency Challenge ✨ ✍️My 4 Go-To JavaScript Heavy Hitter🚀: As a developer, there are a few JavaScript features I keep returning to because they solve common problems elegantly and efficiently. Here are my top four: ✅ DOM Manipulation: Mastering this is essential for any dynamic web experience. The event delegation changed the game for me in optimizing listeners! ✅ Array Methods (map, filter, reduce): The functional approach to data transformation. reduce() in particular is incredibly powerful for aggregating data into a single source of truth. ✅Arrow Functions (=>): More than just concise syntax; they provide lexical scoping of the this keyword, making asynchronous code cleaner and less error-prone. ✅ setTimeout & set Interval: Key to creating dynamic timing and non-blocking asynchronous operations within the browser environment. Understanding the Event Loop here is crucial! **What JS features do you rely on most in your day-to-day coding? Share below! 👇 #JavaScript #WebDevelopment #CodeEffeciently

Tell me about JavaScript 𝗽𝗿𝗶𝗺𝗶𝘁𝗶𝘃𝗲 𝘁𝘆𝗽𝗲𝘀: In JavaScript there are 7 primitive types: 𝗻𝘂𝗹𝗹, 𝘂𝗻𝗱𝗲𝗳𝗶𝗻𝗲𝗱, 𝘀𝘁𝗿𝗶𝗻𝗴, 𝗻𝘂𝗺𝗯𝗲𝗿, 𝗯𝗼𝗼𝗹𝗲𝗮𝗻, 𝘀𝘆𝗺𝗯𝗼𝗹, 𝗯𝗶𝗴𝗶𝗻𝘁. All primitive types are 𝗶𝗺𝗺𝘂𝘁𝗮𝗯𝗹𝗲, that is, they cannot be altered. They don't have methods, but they behave like they do. When properties are accessed on primitives, JavaScript 𝗮𝘂𝘁𝗼-𝗯𝗼𝘅𝗲𝘀 the value into a wrapper object. It makes possible to run some operations over the value, like 𝘁𝗼𝗙𝗶𝘅𝗲𝗱 in Number or 𝗰𝗵𝗮𝗿𝘁𝗔𝘁 in String. The object is discarded right after the operation completes. When passing a primitive value to a 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻, a copy of the value will be passed. This means that the original value and the value passed through the function have different space in memory. Use the comments if you have some addition or a simpler way to explain this. #javascript #techinterview #jobinterview #question #interviewquestion

#JavaScriptErrorHandling When an uncaught error occurs in a JavaScript file, the execution of the current script or function will stop at the point of the error, and any subsequent code within that same execution path will not be executed. Errors and Code Execution: Uncaught Errors: If an error is thrown and not handled by a try...catch block, it will typically halt the execution of the current script or function. Errors within try...catch blocks: If an error occurs within a try block, the execution will jump to the corresponding catch block, allowing you to handle the error and potentially continue execution after the catch block or in a finally block. Event-driven execution: In a web browser environment, JavaScript is often event-driven. An error in one event handler will typically stop the execution of that specific handler, but other independent event handlers or scripts might still execute if they are triggered by other events. Multiple script files: If an error occurs in one JavaScript file, it will not automatically stop the execution of other, independently loaded and executed JavaScript files, unless those files are dependent on the failing file or the error is a critical global error that crashes the entire JavaScript engine. #javascript #error #codeExecution

🚀 𝗨𝗻𝗱𝗲𝗿𝘀𝘁𝗮𝗻𝗱𝗶𝗻𝗴 𝗣𝗿𝗼𝘅𝘆 𝗶𝗻 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 ⤵️ Recently, I was studying about Proxy in JavaScript and here’s what I’ve learned 👇 ⇾ What is 𝗽𝗿𝗼𝘅𝘆? A Proxy lets you wrap an object and control what happens when someone reads, writes, or modifies its properties. Proxy objects are commonly used to log property accesses, validate, format, or sanitize inputs, and so on. You can create a Proxy with two parameters:  • 𝙩𝙖𝙧𝙜𝙚𝙩: the original object which you want to proxy.  • 𝙝𝙖𝙣𝙙𝙡𝙚𝙧: an object that defines which operations will be intercepted and how to redefine intercepted operations. ⇾ 𝙜𝙚𝙩 - when a property is read Controls what happens when someone tries to access a property. ⇾ 𝙨𝙚𝙩 - when a property is modified Controls what happens when someone tries to assign a property. #JavaScript #WebDevelopment #FrontendDevelopment #CodingJourney #LearnInPublic

#Javascript #Linkedin #interviewpractices #simpleanswer What is Prototype? Ans: When an object doesn’t have a property or method, it will look into its prototype to find it. So prototype helps share methods between objects without copying them again and again. In short: Prototype is like a shared storage of properties and methods for objects.

👇 The Core Issue (Don't peek until you've thought about it!) The problem lies with JavaScript's falsy values. In the condition if (!name || !favoriteNumber) return, the value 0 for favoriteNumber is treated as falsy. Because of this, when the function is called as createUser('John', 0), the condition !favoriteNumber evaluates to !0, which is true. The function hits the return statement early, resulting in undefined being logged instead of the valid user object. ✅ The Fix To correctly validate the input, you should check specifically for values that genuinely indicate missing input, such as undefined or null, rather than relying on the general falsy check. The fix uses the abstract equality operator (==) which conveniently checks for both null and undefined in a single comparison (value == null): // Only return if name or favoriteNumber is actually missing (null/undefined) if (name == null || favoriteNumber == null) return This allows valid values like 0 or an empty string '' to pass the check while still preventing the function from running with truly missing parameters. 💡 Why This Matters This is a classic technical interview question that directly tests your understanding of JavaScript's type coercion and falsy values (0, '', null, undefined, NaN, false). Misunderstanding this can lead to subtle, frustrating bugs that are hard to track down! Reference: Article from WebDevSimplified: https://lnkd.in/dQPQqdzz #JavaScript #InterviewPrep #WebDevelopment #SoftwareEngineer #CodingTips #JS #CodeQuality #itsmacr8

The JavaScript filter() method is a powerful way to create a new array containing only the elements that meet a certain condition. It goes through each item in the array and returns the ones that pass the test you provide. For example, to get all even numbers from an array: javascript const numbers = [1, 2, 3, 4, 5]; const evens = numbers.filter(num => num % 2 === 0); console.log(evens); // Output: [2, 4] Use filter() whenever you need to sift through data and extract only what’s relevant, making your code more declarative and concise! #JavaScript #WebDevelopment #CodingTips #ArrayMethods

Came across a really clear article on the JavaScript Event Loop: “𝐓𝐡𝐞 𝐉𝐚𝐯𝐚𝐒𝐜𝐫𝐢𝐩𝐭 𝐄𝐯𝐞𝐧𝐭 𝐋𝐨𝐨𝐩 𝐄𝐱𝐩𝐥𝐚𝐢𝐧𝐞𝐝 𝐰𝐢𝐭𝐡 𝐄𝐱𝐚𝐦𝐩𝐥𝐞𝐬” short and practical. Great refresher on async tasks, microtasks vs macrotasks, and how the event loop works. The examples make it easy to connect theory with real code. If you work with JS, definitely worth a read! 🔗 https://lnkd.in/gwqhBxim #JavaScript #FrontendDevelopment #WebDevelopment #DeveloperLearning #React #EventLoop