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Remove Array Duplicates
basicjavascript
Background
Deduplication is critical in data cleaning, set operations, and preventing redundant processing of elements.
Problem
Write a function that takes an array and returns a new array with all duplicate values removed, preserving the order of first appearance.
Input
An array of primitive values (numbers, strings, booleans).
Output
A new array with duplicates removed, preserving first-occurrence order.
Sample tests
Sample 1
Input: [1, 2, 2, 3, 1, 4]
Expected: [1, 2, 3, 4]
Your solution
Learning objective
Learn to use Set for efficient deduplication and understand order preservation.