JavaScript Event Loop: Understanding Async Code Execution

JavaScript Event Loop – Quick Example Understanding the Event Loop is important for writing efficient asynchronous JavaScript. Example: console.log("Start") const prom = new Promise((res) => res(true)) setTimeout(() => console.log("setTimeout"), 0) process.nextTick(() => console.log("nextTick")) queueMicrotask(() => console.log("microtask")) console.log(prom) Output order will be: Start Promise { true } nextTick microtask setTimeout Why? Because JavaScript processes tasks in this order: 1. Synchronous code 2. Microtasks (nextTick, Promises, queueMicrotask) 3. Macrotasks (setTimeout, setImmediate) Understanding this helps when debugging async issues in frontend apps. #javascript #webdevelopment #frontend #vuejs #eventloop

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