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Why array.includes() Can Slow Down Your JavaScript at Scale

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A JavaScript performance discussion highlights how commonly used methods like array.includes() can become bottlenecks when applied repeatedly to large datasets. The issue is compounded when such methods are nested inside loops, significantly increasing computational overhead. The author illustrates these trade-offs using plain JavaScript and React examples to show real-world impact. Alternative data structures like Set and Map are presented as more efficient choices in specific scenarios. The key takeaway is not to over-optimize, but to understand when a simple structural change can meaningfully improve code performance.

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Why array.includes() Can Slow Down Your JavaScript at Scale · ShortSingh