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

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

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

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.

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

npm install array-iterate

In Deno with esm.sh:

import {arrayIterate} from 'https://esm.sh/array-iterate@2'

In browsers with esm.sh:

<script type="module">
  import {arrayIterate} from 'https://esm.sh/array-iterate@2?bundle'
</script>

import {arrayIterate} from 'array-iterate'

let first = true

arrayIterate(
  [1, 2, 3, 4],
  function (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]

This package exports the identifier arrayIterate. There is no default export.

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.

• 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 passed as this in callbackFn

undefined.

Callback given to iterate.

• 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

The optional index to move to next (number or undefined)

This package is fully typed with TypeScript. It exports the additional type CallbackFn.

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

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

Yes please! See How to Contribute to Open Source.

MIT © Titus Wormer