iterable-ops

iterable-ops

Lazy utility functions for sync and async iterables — map, filter, take, chunk, zip, flatten

Install

npm install iterable-ops

Usage

import {map, filter, take, chunk, zip, flatten, unique} from 'iterable-ops';

[...map([1, 2, 3], x => x * 2)];
//=> [2, 4, 6]

[...filter([1, 2, 3, 4], x => x % 2 === 0)];
//=> [2, 4]

[...take([1, 2, 3, 4, 5], 3)];
//=> [1, 2, 3]

[...chunk([1, 2, 3, 4, 5], 2)];
//=> [[1, 2], [3, 4], [5]]

[...zip([1, 2], ['a', 'b'])];
//=> [[1, 'a'], [2, 'b']]

[...flatten([[1, 2], [3, [4]]])];
//=> [1, 2, 3, [4]]

[...unique([1, 2, 2, 3, 3])];
//=> [1, 2, 3]

All functions are lazy — they use generators and only compute values as they are consumed.

API

map(iterable, function_)

Yields function_(item) for each item.

filter(iterable, function_)

Yields items where function_(item) is truthy.

take(iterable, count)

Yields the first count items, then stops.

drop(iterable, count)

Skips the first count items, then yields the rest.

chunk(iterable, size)

Yields arrays of size items. The last chunk may be smaller.

zip(...iterables)

Yields arrays of parallel items from each iterable. Stops at the shortest.

flatten(iterable, depth?)

Yields items from nested iterables, flattening up to depth levels. Default: 1.

unique(iterable)

Yields only the first occurrence of each value.

mapAsync(iterable, function_)

Async version of map for async iterables.

filterAsync(iterable, function_)

Async version of filter for async iterables.

Related

• map-extras - Utility functions for JavaScript Map

License

MIT