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dropRight()

dropRight<T>(array, count): T[]

Creates a slice of array with n elements dropped from the end.

Type Parameters​

T: T​

The type of elements in the array.

Parameters​

array: readonly T[]​

The array to query.

count: number​

The number of elements to drop.

Returns: T[]​

A new array with the last count elements removed.

Throws​

RangeError If count is negative.

Since​

2.0.0

Performance​

O(n) time & space, single slice operation.

Also known as​

dropLast (Remeda, Ramda) · dropRight (Lodash, es-toolkit, Effect) · ❌ (Radashi, Modern Dash, Antfu)

Example​

const numbers = [1, 2, 3, 4, 5];

dropRight(numbers, 2);
// => [1, 2, 3]

dropRight(numbers, 0);
// => [1, 2, 3, 4, 5]

How it works?​

Drops elements from the end instead of the beginning.

Use Cases​

Remove incomplete trailing data 📌​

Exclude the last N entries that may be partial or unfinished. Perfect for real-time data streams or live metrics.

const liveMetrics = [
  { minute: "10:01", value: 150 },
  { minute: "10:02", value: 148 },
  { minute: "10:03", value: 152 },
  { minute: "10:04", value: 45 }, // Incomplete minute
];

const completeData = dropRight(liveMetrics, 1);
// => First 3 entries only

Exclude future-dated entries​

Remove scheduled or draft items from the end of sorted lists. Useful for publishing systems or event calendars.

const posts = [
  { title: "Published 1", date: "2025-01-10" },
  { title: "Published 2", date: "2025-01-15" },
  { title: "Scheduled", date: "2025-02-01" },
  { title: "Draft", date: "2025-03-01" },
];

const liveContent = dropRight(posts, 2);
// => Only published posts

Trim trailing placeholders from fixed-length records​

Remove padding or filler values from data structures. Essential for parsing binary formats or legacy systems.

const record = ["John", "Doe", "john@mail.com", "", "", ""];

const cleanRecord = dropRight(record, 3);
// => ["John", "Doe", "john@mail.com"]