JavaScript Lesson 23 | Promises | Promise Chaining, Promise.all, Promise.race & Error handling скачать в хорошем качестве

JavaScript Lesson 23 | Promises | Promise Chaining, Promise.all, Promise.race & Error handling

#javascript #promises #async Lesson 23: Promises in JavaScript: how to create promises, promise states (pending/fulfilled/rejected), chaining with .then(), error handling with .catch(), .finally(), and utility helpers: Promise.all, Promise.race and Promise.allSettled. Includes practical examples: immediate resolve/reject, chaining async calls, Promise.all vs Promise.race, and handling rejections. What you’ll learn: • Create promises with new Promise(resolve,reject) and use Promise.resolve/Promise.reject • Promise chaining: return values from .then() and sequencing async steps • Error handling: .catch() for rejection and .finally() for cleanup • Promise combinators: Promise.all, Promise.race, Promise.allSettled — when to use each • Patterns for fetching dependent async data (fetchUser → fetchPosts → fetchComments) and avoiding callback hell