@rbxts/jsnatives

Array.reverse

Reverses an array in place and returns the reference to the same array.

Signature

function reverse<T>(array: Array<T>): Array<T>

Description

The Array.reverse() method reverses an array in place. The first array element becomes the last, and the last array element becomes the first. This method mutates the original array and returns a reference to the same array.

Examples

Basic reversal

const array = [1, 2, 3, 4, 5];
const reversed = ArrayUtils.reverse(array);

print(array); // [5, 4, 3, 2, 1]
print(reversed); // [5, 4, 3, 2, 1]
print(array === reversed); // true - both reference the same array

Reversing arrays with different types

const mixedArray = [1, "two", true, { key: "value" }];
ArrayUtils.reverse(mixedArray);

print(mixedArray); // [{ key: "value" }, true, "two", 1]

Reversing empty arrays

const emptyArray = [];
ArrayUtils.reverse(emptyArray);

print(emptyArray); // [] - an empty array remains empty

Using reverse in a chain of operations

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

// Filter out odd numbers, double the values, then reverse
const result = ArrayUtils.reverse(
  array
    .filter(x => x % 2 === 0)
    .map(x => x * 2)
);

print(result); // [8, 4] (from original even numbers [2, 4] -> doubled [4, 8] -> reversed [8, 4])

Comparison with toReversed

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

// reverse() mutates the original array
const mutatedArray = ArrayUtils.reverse(original);
print(original); // [5, 4, 3, 2, 1]
print(mutatedArray); // [5, 4, 3, 2, 1]
print(original === mutatedArray); // true - same array reference

// To reverse without mutation, use toReversed() or create a copy first
const copied = [...original];
const reversedCopy = ArrayUtils.reverse(copied);
print(original); // [5, 4, 3, 2, 1] - still reversed from before
print(copied); // [1, 2, 3, 4, 5] -> [5, 4, 3, 2, 1] - copy was reversed
print(reversedCopy); // [5, 4, 3, 2, 1]
print(copied === reversedCopy); // true - same array reference