Array Helpers

Utility functions for working with array operations.

Functions

Function	Description
cartesianProduct	Computes the Cartesian product of the provided arrays.
chunk	Chunks an array into smaller arrays of specified size.
combineSortFns	Chains multiple sort functions into a single comparator: the first function decides the order unless it reports a tie (…
compact	Removes all falsy values (`false`, `null`, `undefined`, `0`, `“”`, `NaN`) from an array.
countBy	Groups the elements of an array by the key returned by `keyFn` and returns a record mapping each key to the number of m…
createSortByBooleanFn	Creates a sort function for objects by a boolean property.
createSortByDateFn	Creates a sort function for objects by date property.
createSortByNaturalFn	Creates a sort function for objects by one or more string properties using natural ordering.
createSortByNumberFn	Creates a sort function for objects by number property.
createSortByStringFn	Creates a sort function for objects by one or more string properties.
difference	Returns the difference between two arrays (items in first array but not in second).
drop	native JS Array.prototype.slice(n) (ES3)
ensureArray	Wraps a value in an array if it is not already one.
equalsDeep	Recursive structural array equality.
equalsShallow	Positional, one-level (shallow) array equality.
equalsUnordered	Order-independent (set-style) array equality.
filterAsync	The async counterpart to `Array.prototype.filter`: runs `predicate` for every item and resolves to the items whose pred…
find / findIndex	native JS Array.prototype.find() / findIndex() (ES2015)
flatten / flat	native JS Array.prototype.flat(depth?) (ES2019)
forEachAsync	The async counterpart to `Array.prototype.forEach`: runs `fn` for every item for its side effects, discarding any retur…
groupBy / group	native JS Object.groupBy(arr, fn) (ES2024)
head / first	native JS Array.prototype.at(0) (ES2022)
includes	native JS Array.prototype.includes() (ES2016)
intersection	Compute the intersection of two arrays, meaning the elements that are present in both arrays.
intersects	Simple helper that check if two lists shared at least an item in common.
isEmpty	Checks if an array is empty (has no elements).
isNonEmpty	Checks if an array is non-empty (has at least one element).
last	native JS Array.prototype.at(-1) (ES2022)
mapAsync	The async counterpart to `Array.prototype.map`: applies `fn` to every item and resolves to an array of the results, in …
max	Returns the maximum value in an array using a loop instead of spread, avoiding the call stack overflow that occurs with…
mean	Calculates the arithmetic mean (average) of an array of numbers.
meanBy	Calculates the arithmetic mean of numbers derived from each item of an array via an iteratee.
median	Calculates the median (middle value) of an array of numbers.
min	Returns the minimum value in an array using a loop instead of spread, avoiding the call stack overflow that occurs with…
partition	Splits an array into two groups based on a predicate function.
percentile	Calculates the p-th percentile of an array of numbers using linear interpolation between the closest ranks.
range	Generates an array of sequential numbers from start to end (exclusive).
replaceOrAppend	Returns a new array with the first item matching `predicate` replaced by `item` — or `item` appended at the end if no m…
reverse	native JS Array.prototype.toReversed() (ES2023)
sample	Picks one or more random elements from an array.
select	Filters and transforms an array in a single pass.
select / filterMap	native JS Array.prototype.filter().map() (ES5)
shuffle	Randomly reorders elements of an array using the Fisher-Yates algorithm.
sort (immutable)	native JS Array.prototype.toSorted(compareFn?) (ES2023)
sortBy / orderBy	native JS Array.prototype.toSorted(fn?) (ES2023)
sortNumberAscFn	Sort numbers in ascending order
sortNumberDescFn	Sort numbers in descending order
sortStringAscFn	Sort strings in ascending order
sortStringAscInsensitiveFn	Sort strings in ascending order (case insensitive)
sortStringDescFn	Sort strings in descending order
sortStringNaturalAscFn	Sort strings in ascending order using natural (human-friendly) ordering.
sortStringNaturalAscInsensitiveFn	Sort strings in ascending natural order, ignoring case **and diacritics** (`Intl.Collator { sensitivity: ‘base’ }` — tr…
sortStringNaturalDescFn	Sort strings in descending order using natural (human-friendly) ordering.
sortStringNaturalDescInsensitiveFn	Sort strings in descending natural order, ignoring case **and diacritics** (`Intl.Collator { sensitivity: ‘base’ }` — t…
sum	Calculates the sum of an array of numbers.
sumBy	Calculates the sum of numbers derived from each item of an array via an iteratee.
symmetricDifference	Returns the symmetric difference between two arrays: items present in exactly one of the two arrays (in either, but not…
tail	native JS Array.prototype.slice(1) (ES3)
take	native JS Array.prototype.slice(0, n) (ES3)
toggle	Returns a new array with `item` removed if present, or appended if absent — the common “toggle a selection” pattern.
union	native JS unique([...a, ...b]) (ES2015)
unique	Removes duplicate values from an array.
unzip	Splits an array of tuples into separate arrays, one per position.
without	Returns a new array with all occurrences of the given values removed.
zip	Combines multiple arrays element-by-element into an array of tuples.