array-iterate

Array#forEach() but it’s possible to define where to move to next.

Contents

• What is this?
• When should I use this?
• Install
• Use
• API
  • arrayIterate(values, callbackFn[, thisArg])
• Types
• Compatibility
• Security
• Contribute
• License

What is this?

A tiny package that works just like forEach, with one small difference.

When should I use this?

You can use this if for some weird reason—like I did—you have to sometimes skip a few places ahead or backwards when moving through an array.

Install

This package is ESM only. In Node.js (version 12.20+, 14.14+, or 16.0+), install with npm:

npm install array-iterate

In Deno with Skypack:

import {arrayIterate} from 'https://cdn.skypack.dev/array-iterate@2?dts'

In browsers with Skypack:

<script type="module">
  import {arrayIterate} from 'https://cdn.skypack.dev/array-iterate@2?min'
</script>

Use

import {arrayIterate} from 'array-iterate'

let first = true

arrayIterate(
  [1, 2, 3, 4],
  (value, index, values) => {
    console.log(this, value, index, values)

    // Repeat once.
    if (first && index + 1 === values.length) {
      first = false
      return 0
    }
  },
  {hello: 'world'}
)

Yields:

{hello: 'world'}, 1, 0, [1, 2, 3, 4]
{hello: 'world'}, 2, 1, [1, 2, 3, 4]
{hello: 'world'}, 3, 2, [1, 2, 3, 4]
{hello: 'world'}, 4, 3, [1, 2, 3, 4]
{hello: 'world'}, 1, 0, [1, 2, 3, 4]
{hello: 'world'}, 2, 1, [1, 2, 3, 4]
{hello: 'world'}, 3, 2, [1, 2, 3, 4]
{hello: 'world'}, 4, 3, [1, 2, 3, 4]

API

This package exports the following identifiers: arrayIterate. There is no default export.

arrayIterate(values, callbackFn[, thisArg])

Perform the specified action for each element in an array (just like Array#forEach()). When callbackFn returns a number, moves to the element at that index next.

Parameters

• values (Array<*>) — values to iterate over
• callbackFn (Function) — function called for each element, can return the index to move to next
• thisArg (*, optional) — optional object assigned as this in callbackFn

Returns

undefined.

function callbackFn(value, index, values)

Callback given to iterate.

Parameters

• this (*) — context object when given as thisArg to arrayIterate or undefined
• value (*) — element in array
• index (number) — index of value in values
• values (Array.<*>) — list

Returns

number or undefined — the index to move to next.

Types

This package is fully typed with TypeScript. There is also a CallbackFn type export that represents the callback function.

Compatibility

This package is at least compatible with all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, and 16.0+. It also works in Deno and modern browsers.

Security

This package is safe, assuming that you don’t create an infinite loop by keeping on repeating.

Contribute

Yes please! See How to Contribute to Open Source.

License

MIT © Titus Wormer