Data Scientist Documents Journey Learning JavaScript Promises and Async Behavior

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A data scientist with a Python and R background is documenting their experience learning JavaScript development from scratch, drawing parallels to familiar concepts. The author explores JavaScript Promises and the async/await pattern, contrasting them with Python's blocking operations like time.sleep() and Selenium's WebDriverWait. A key insight shared is that JavaScript's asynchronous model keeps the rest of the program running during a wait, unlike Python's single-threaded blocking approach that pauses all execution. This difference produces an unexpected output order, where synchronous code runs before an awaited async result is returned. The post is part of a beginner-focused series aimed at helping data professionals transition into software development.

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