Now and .then: Debugging Async JS
summary
Concrete debugging recipes and gotchas: a callback that returns undefined because readFile runs asynchronously, a Promise wrapper that silently succeeds because it never rejects, and a .then/.catch ordering bug that still runs downstream handlers. Uses console.log for quick probes and the Chrome DevTools debugger to step through async flow. Highlights that async functions return promises, that refactors can turn parallel work into blocking awaits, and urges the rule always reject and practicing failure modes to learn what breaks.
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chapters (9)
- 0:00Start
- 1:17Why Is Debugging Asynchronous Code So Difficult
- 1:46Examples of Async Bugs
- 2:57Get Config Function
- 11:10Silent Error
- 14:06The Debugger
- 19:24Promises and Async Await
- 20:56Break Point
- 21:36Async Functions Return Promises
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