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    JavaScript

    Functional Array Utilities You Should Know

    Small, pure helpers that make working with arrays expressive and bug-free.

    5 min readMay 20, 2026

    Deduplicate with Set

    The Set constructor removes duplicates in a single expression.

    JavaScript
    const unique = arr => [...new Set(arr)];

    Chunk an Array

    Split an array into evenly sized pieces — useful for pagination and batching.

    JavaScript
    const chunk = (arr, size) =>
  Array.from({ length: Math.ceil(arr.length / size) },
    (_, i) => arr.slice(i * size, i * size + size)
  );