uniqBy

uniqBy<T, U>(iterable, keyOf, comparisonStrategy?): IterableIterator<T>

Defined in: set/uniq-by.ts:30

Yields the first item seen for each distinct keyOf(item), in first-occurrence order.

Time complexity: O(n) under the default "sameValueZero".

Type Parameters

T

T

U

U

Parameters

iterable

Iterable<T>

The input iterable.

keyOf

Callable<[T], U>

A function that takes an item and returns a key.

comparisonStrategy?

EqualityComparisonStrategy<U, U> = "sameValueZero"

The equality comparison strategy for keys.

Returns

IterableIterator<T>

An iterator over the first item seen for each distinct key.

Example

  const array = [
    { id: 1, name: "Alice" },
    { id: 2, name: "Bob" },
    { id: 1, name: "Alice" },
  ];
  [...uniqBy(array, (item) => item.id)];
  // [{ id: 1, name: "Alice" }, { id: 2, name: "Bob" }]
  ```;