Reduce() Polyfill From Scratch | Ace Your JavaScript Interview
Learn how the JavaScript reduce() method actually works internally by building your own reduce polyfill from scratch.
In this video, we’ll understand:
• How Array.reduce() works
• What accumulator and currentValue mean
• How initial values work in reduce
• Why iteration starts from index 1 sometimes
• How reduce handles sparse arrays
• How to create a custom myReduce() method using Array.prototype
This is a very common JavaScript interview question asked in companies like Apple, Amazon and ByteDance.
If you’re preparing for JavaScript interviews or want to deeply understand JavaScript internals, this video will help a lot.
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