iterable-operator
Advanced tools
Readme
Utilities for JavaScript Iterable and AsyncIterable.
npm install --save iterable-operator
# or
yarn add iterable-operator
import { map, toArray } from 'iterable-operator'
const iter = [1, 2, 3]
const doubleIter = map(iter, x => x * 2)
const result = toArray(doubleIter)
import { IterableOperator } from 'iterable-operator/lib/es2018/style/chaining'
const result = new IterableOperator([1, 2, 3])
.map(x => x * 2)
.toArray()
It is prepared for bind-operator.
import { map, toArray } from 'iterable-operator/lib/es2018/style/binding'
const result = [1, 2, 3]
::map(x => x * 2)
::toArray()
It is prepared for pipeline-operator.
import { map, toArray } from 'iterable-operator/lib/es2018/style/pipeline'
const result = [1, 2, 3]
|> map(x => x * 2)
|> toArray()
There are two kinds of operators:
function chunk<T>(iterable: Iterable<T>, size: number): Iterable<T[]>
function chunkAsync<T>(iterable: AsyncIterable<T>, size: number): AsyncIterable<T[]>
// size > 0
chunk([1, 2, 3], 2) // [[1, 2], [3]]
chunk([1, 2, 3], 3) // [[1, 2, 3]]
chunk([1, 2, 3], 5) // [[1, 2, 3]]
chunk([1, 2, 3], 0) // throw Error
chunk([1, 2, 3], -1) // throw Error
The memory usage of this function depends on size.
function chunkBy<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): Iterable<T[]>
function chunkByAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): AsyncIterable<T[]>
chunkBy([1, 2, 3], x => x === 2) // [[1, 2], [3]]
chunkBy([1, 2, 3], x => x === 3) // [[1, 2, 3]]
chunkBy([1, 2, 3], x => x === 5) // [[1, 2, 3]]
The memory usage of this function depends on iterable and predicate.
function concat<T, U>(
iterable: Iterable<T>
, ...otherIterables: Iterable<U>[]
): Iterable<T | U> {
function concatAsync<T, U>(
iterable: Iterable<T | PromiseLike<T>> | AsyncIterable<T>
, ...otherIterables: Array<Iterable<U | PromiseLike<U>> | AsyncIterable<U>>
): AsyncIterable<T | U> {
concat([1, 2, 3]) // [1, 2, 3]
concat([1, 2, 3], ['a', 'b', 'c']) // [1, 2, 3, 'a', 'b', 'c']
function drop<T>(iterable: Iterable<T>, count: number): Iterable<T>
function dropAsync<T>(iterable: AsyncIterable<T>, count: number): AsyncIterable<T>
// count >= 0
drop([1, 2, 3], 0) // [1, 2, 3]
drop([1, 2, 3], 2) // [3]
drop([1, 2, 3], 3) // []
drop([1, 2, 3], 5) // []
drop([1, 2, 3], -1) // throw Error
function dropRight<T>(iterable: Iterable<T>, count: number): Iterable<T>
function dropRightAsync<T>(iterable: AsyncIterable<T>, count: number): AsyncIterable<T>
// count >= 0
dropRight([1, 2, 3], 0) // [1, 2, 3]
dropRight([1, 2, 3], 2) // [1]
dropRight([1, 2, 3], 3) // []
dropRight([1, 2, 3], 5) // []
dropRight([1, 2, 3], -1) // throw Error
The memory usage of this function depends on iterable.
function dropUntil<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): Iterable<T>
function dropUntilAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => boolean | PromiseLike<boolean>
): AsyncIterable<T>
dropUntil([1, 2, 3], x => x === 2) // [2, 3]
The memory usage of this function depends on iterable and predicate.
function filter<T, U extends T = T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): Iterable<U>
function filterAsync<T, U extends T = T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): AsyncIterable<U>
filter([1, 2, 3], x => x % 2 === 1) // [1, 3]
function flatten<T>(iterable: Iterable<unknown>): Iterable<T>
function flattenAsync<T>(iterable: AsyncIterable<unknown>): AsyncIterable<T>
flatten([]) // []
flatten('123') // ['1', '2', '3']
flatten(['one', ['two'], 0, [1, [2]]]) // ['o', 'n', 'e', 'two', 0, 1, [2]]
function flattenDeep<T>(iterable: Iterable<unknown>, depth: number = Infinity): Iterable<T>
function flattenDeepAsync<T>(
iterable: AsyncIterable<unknown>
, depth: number = Infinity
): AsyncIterable<T>
// depth >= 0
flattenDeep([]) // []
flattenDeep('123') // ['1', '2', '3']
flattenDeep([], -1) // throw Error
flattenDeep([0, [1]], 0) // [0, [1]]
flattenDeep(['one', ['two', ['three']], 0, [1, [2, [3]]]], 2) // ['o', 'n', 'e', 't', 'w', 'o', 'three', 0, 1, 2, [3]]
function flattenBy<T>(
iterable: Iterable<unknown>
, predicate: (element: unknown, level: number) => boolean
): Iterable<T>
function flattenByAsync<T>(
iterable: Iterable<unknown> | AsyncIterable<unknown>
, predicate: (element: unknown, level: number) => boolean | PromiseLike<unknown>
): AsyncIterable<T>
flattenBy(['one', ['two'], 0, [1]], x => typeof x !== 'string') // ['one', 'two', 0, 1]
flattenBy([], () => true) // []
flattenBy('123', () => true) // ['1', '2', '3']
function map<T, U>(
iterable: Iterable<T>
, fn: (element: T, index: number) => U
): Iterable<U>
function mapAsync<T, U>(
iterable: Iterable<T> | AsyncIterable<T>
, fn: (element: T, index: number) => U | PromiseLike<U>
): AsyncIterable<U>
map([1, 2, 3], x => x * 2) // [2, 4, 6]
function repeat<T>(iterable: Iterable<T>, times: number): Iterable<T>
function repeatAsync<T>(iterable: AsyncIterable<T>, times: number): AsyncIterable<T>
// times >= 0
repeat([1, 2, 3], 2) // [1, 2, 3, 1, 2, 3]
repeat([1, 2, 3], 0) // []
repeat([1, 2, 3], -1) // throw Error
The memory usage of this function depends on iterable.
function slice<T>(
iterable: Iterable<T>
, start: number
, end: number = Infinity
): Iterable<T>
function sliceAsync<T>(
iterable: AsyncIterable<T>
, start: number
, end: number = Infinity
): AsyncIterable<T>
// start >= 0, end >= start
slice([1, 2, 3], -1, 1) // throw Error
slice([1, 2, 3], 3, 5) // []
slice([1, 2, 3], 1, 2) // [2]
slice([1, 2, 3], 1, 1) // []
slice([1, 2, 3], 2, 1) // throw Error
function split<T>(iterable: Iterable<T>, separator: T): Iterable<T[]>
function splitAsync<T>(iterable: AsyncIterable<T>, separator: T): AsyncIterable<T[]>
split([1, 2, 3, 4, 5], 3) // [[1, 2], [4, 5]]
split([1, 2, 3, 4, 5], 1) // [[], [2, 3, 4, 5]]
split([1, 2, 3, 4, 5], 5) // [[1, 2, 3, 4], []]
split([1, 2, 3, 4, 5], 0) // [[1, 2, 3, 4, 5]]
The memory usage of this function depends on iterable and separator.
function splitBy<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): Iterable<T[]>
function splitByAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): AsyncIterable<T[]>
splitBy([1, 2, 3, 4, 5], x => x === 3) // [[1, 2], [4, 5]]
splitBy([1, 2, 3, 4, 5], x => x === 1) // [[], [2, 3, 4, 5]]
splitBy([1, 2, 3, 4, 5], x => x === 5) // [[1, 2, 3, 4], []]
splitBy([1, 2, 3, 4, 5], x => x === 0) // [[1, 2, 3, 4, 5]]
The memory usage of this function depends on iterable and predicate.
function take<T>(iterable: Iterable<T>, count: number): Iterable<T>
function takeAsync<T>(iterable: AsyncIterable<T>, count: number): AsyncIterable<T>
take([1, 2, 3], 5) // [1, 2, 3]
take([1, 2, 3], 2) // [1, 2]
take([1, 2, 3], 0) // []
take([1, 2, 3], -1) // throw Error
function takeRight<T>(iterable: Iterable<T>, count: number): Iterable<T>
function takeRightAsync<T>(iterable: AsyncIterable<T>, count: number): AsyncIterable<T>
takeRight([1, 2, 3], 2) // [2, 3]
takeRight([1, 2, 3], 5) // [1, 2, 3]
takeRight([1, 2, 3], 0) // []
takeRight([1, 2, 3], -1) // throw Error
The memory usage of this function depends on count.
function takeUntil<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): Iterable<T>
function takeUntilAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): AsyncIterable<T>
takeUntil([1, 2, 3], x => x === 2) // [1]
function tap<T>(
iterable: Iterable<T>
, fn: (element: T, index: number) => unknown
): Iterable<T> {
function tapAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, fn: (element: T, index: number) => unknown | PromiseLike<unknown>
): AsyncIterable<T>
tap([1, 2, 3], x => console.log(x)) // [1, 2, 3]
function toAsyncIterable<T>(iterable: Iterable<T | PromiseLike<T>>): AsyncIterable<T>
toAsyncIterable([1, 2, 3]) // AsyncIterable [1, 2, 3]
function transform<T, U>(
iterable: Iterable<T>
, transformer: (iterable: Iterable<T>) => Iterable<U>
): Iterable<U>
function transformAsync<T, U>(
iterable: Iterable<T>
, transformer: (iterable: Iterable<T>) => AsyncIterable<U>
): AsyncIterable<U>
function transformAsync<T, U>(
iterable: AsyncIterable<T>
, transformer: (iterable: AsyncIterable<T>) => AsyncIterable<U>
): AsyncIterable<U>
transform([1, 2, 3], function* double(iter) {
for (const element of iter) {
yield element * 2
}
}) // [2, 4, 6]
function uniq<T>(iterable: Iterable<T>): Iterable<T>
function uniqAsync<T>(iterable: AsyncIterable<T>): AsyncIterable<T>
uniq([1, 1, 2, 2, 3, 3]) // [1, 2, 3]
The memory usage of this function depends on iterable.
function uniqBy<T, U>(
iterable: Iterable<T>
, fn: (element: T, index: number) => U
): Iterable<T> {
function uniqByAsync<T, U>(
iterable: Iterable<T> | AsyncIterable<T>
, fn: (element: T, index: number) => U | PromiseLike<U>
): AsyncIterable<T>
uniqBy([1, 2, 3], x => x % 2) // [1, 2]
The memory usage of this function depends on fn.
function zip<T, U extends Array<Iterable<unknown>>>(
iterable: Iterable<T>
, ...otherIterables: U
): Iterable<[T, ...ExtractTypeTupleFromIterableTuple<U>]> {
function zipAsync<T, U extends Array<Iterable<unknown> | AsyncIterable<unknown>>>(
iterable: Iterable<T | PromiseLike<T>> | AsyncIterable<T>
, ...otherIterables: U
): AsyncIterable<[T, ...ExtractTypeTupleFromAsyncLikeIterableTuple<U>]> {
zip([1, 2, 3], ['a', 'b', 'c']) // [[1, 'a'], [2, 'b'], [3, 'c']]
zip([1, 2, 3], ['a', 'b']) // [[1, 'a'], [2, 'b']
zip([1, 2, 3], ['a', 'b'], ['i', 'ii', 'iii']) // [[1, 'a', 'i'], [2, 'b', 'ii']]
function consume<T, U>(iterable: Iterable<T>, consumer: (iterable: Iterable<T>) => U): U
function consume<T, U>(
iterable: AsyncIterable<T>
, consumer: (iterable: AsyncIterable<T>) => U
): U
consume([1, 2, 3], xs => new Set(xs)) // Set [1, 2, 3]
function each<T>(iterable: Iterable<T>, fn: (element: T, index: number) => unknown): void
function eachAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, fn: (element: T, index: number) => unknown | PromiseLike<unknown>
): Promise<void>
each([1, 2, 3], x => console.log(x)) // void
function every<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): boolean
function everyAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): Promise<boolean>
every([1, 2, 3], x => x < 5) // true
every([1, 2, 3], x => x <= 2) // false
function find<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): T | undefined
function findAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): Promise<T | undefined>
find([1, 2, 3], x => x === 2) // 2
find([1, 2, 3], x => x === 4) // undefined
function first<T>(iterable: Iterable<T>): T | undefined
function firstAsync<T>(iterable: AsyncIterable<T>): Promise<T | undefined>
first([1, 2, 3]) // 1
first([]) // undefined
function includes<T>(iterable: Iterable<T>, value: T): boolean
function includesAsync<T>(iterable: AsyncIterable<T>, value: T): Promise<boolean>
includes([1, 2, 3], 2) // true
includes([1, 2, 3], 4) // false
function last<T>(iterable: Iterable<T>): T | undefined
function lastAsync<T>(iterable: AsyncIterable<T>): Promise<T | undefined>
last([1, 2, 3]) // 3
last([]) // undefined
function match<T>(iterable: Iterable<T>, sequence: ArrayLike<T>): boolean
function matchAsync<T>(
iterable: AsyncIterable<T>
, sequence: ArrayLike<T>
): Promise<boolean>
match([1, 2, 3], [2, 3]) // true
match([1, 2, 3], [3, 2]) // false
match([1, 2, 3], []) // true
function reduce<T, U>(
iterable: Iterable<T>
, fn:
((accumulator: T, currentValue: T, index: number) => T)
& ((accumulator: U, currentValue: T, index: number) => U)
, initialValue?: U
)
function reduceAsync<T, U>(
iterable: Iterable<T> | AsyncIterable<T>
, fn:
((accumulator: T, currentValue: T, index: number) => T | PromiseLike<T>)
& ((accumulator: U, currentValue: T, index: number) => U | PromiseLike<U>)
, initialValue?: U
)
reduce([], (acc, cur) => acc + cur) // throw Error
reduce([1], (acc, cur) => acc + cur) // 1
reduce([1, 2, 3], (acc, cur) => acc + cur) // 6
reduce([1, 2, 3], (acc, cur, index) => {
acc.push([cur, index])
return acc
}) // [[1, 0], [2, 1], [3, 2]]
function some<T>(
iterable: Iterable<T>
, predicate: (element: T, index: number) => unknown
): boolean
function someAsync<T>(
iterable: Iterable<T> | AsyncIterable<T>
, predicate: (element: T, index: number) => unknown | PromiseLike<unknown>
): Promise<boolean>
some([1, 2, 3], x => x === 2) // true
some([1, 2, 3], x => x === 4) // false
function toArray<T>(iterable: Iterable<T>): T[]
function toArrayAsync<T>(iterable: AsyncIterable<T>): Promise<T[]>
toArray([1, 2, 3]) // Array [1, 2, 3]
function toSet<T>(iterable: Iterable<T>): Set<T>
function toSetAsync<T>(iterable: AsyncIterable<T>): Promise<Set<T>>
toSet([1, 1, 2, 2, 3, 3]) // Set [1, 2, 3]
FAQs
Utilities for JavaScript Iterable and AsyncIterable
The npm package iterable-operator receives a total of 515 weekly downloads. As such, iterable-operator popularity was classified as not popular.
We found that iterable-operator demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 1 open source maintainer collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Product
Socket now supports four distinct alert actions instead of the previous two, and alert triaging allows users to override the actions taken for all individual alerts.
Security News
Polyfill.io has been serving malware for months via its CDN, after the project's open source maintainer sold the service to a company based in China.
Security News
OpenSSF is warning open source maintainers to stay vigilant against reputation farming on GitHub, where users artificially inflate their status by manipulating interactions on closed issues and PRs.