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partition

Import from @varavel/vdl-plugin-sdk/utils/arrays.

Utility functions re-exported from es-toolkit (MIT License). See https://github.com/toss/es-toolkit for more details.

Call Signature

function partition<T, U>(arr, isInTruthy): [U[], Exclude<T, U>[]];

Splits an array into two groups based on a predicate function.

This function takes an array and a predicate function. It returns a tuple of two arrays: the first array contains elements for which the predicate function returns true, and the second array contains elements for which the predicate function returns false.

Type Parameters

Type Parameter Description
T The type of elements in the array.
U The type being filtered for.

Parameters

Parameter Type Description
arr readonly T[] The array to partition.
isInTruthy (value, index, array) => value is U A type guard that determines whether an element should be placed in the truthy array. The function is called with each element of the array and its index.

Returns

[U[], Exclude\<T, U>[]]

A tuple containing two arrays: the first array contains elements for which the predicate returned true, and the second array contains elements for which the predicate returned false.

Example

const array = [1, 2, 3, 4] as const;
const isEven = (x: number): x is 2 | 4 => x % 2 === 0;
const [even, odd]: [(2 | 4)[], (2 | 4)[]] = partition(array, isEven);
// even will be [2, 4], and odd will be [1, 3]

Call Signature

function partition<T>(arr, isInTruthy): [T[], T[]];

Splits an array into two groups based on a predicate function.

This function takes an array and a predicate function. It returns a tuple of two arrays: the first array contains elements for which the predicate function returns true, and the second array contains elements for which the predicate function returns false.

Type Parameters

Type Parameter Description
T The type of elements in the array.

Parameters

Parameter Type Description
arr readonly T[] The array to partition.
isInTruthy (value, index, array) => boolean A predicate function that determines whether an element should be placed in the truthy array. The function is called with each element of the array and its index.

Returns

[T[], T[]]

A tuple containing two arrays: the first array contains elements for which the predicate returned true, and the second array contains elements for which the predicate returned false.

Example

const array = [1, 2, 3, 4, 5];
const isEven = x => x % 2 === 0;
const [even, odd] = partition(array, isEven);
// even will be [2, 4], and odd will be [1, 3, 5]