iterateWithTimeout

Loops through every item in an array (or optionally skips some) and calls a function against each element, using a timeout you pass in. Returns a promise which resolves to a new array.

For when you want to asyncronously iterate over an array with a delay, but also get the result from the function being called.

Example usage

npm i iteratetimeout or yarn add iteratetimeout

const iterateWithTimeout = require('iteratetimeout')

import iterateWithTimeout from 'iteratetimeout'

First argument is an array which is your input array, the array you wish to iterate over.**

Second argument is the timeout you wish to wait between each function call.

Third argument is the function you wish to call on each item in the input array.

Fourth (optional) argument is the index you want to start from. (default 0)

Fifth (optional) argument is an array to start with. (default []), each element you return in the function you pass in as the third argument will be pushed to the end of this array.

Returns a new array, not mutating the original (optional) passed in array if you did so.

Simply using it to loop and do something with an interval between each call

async function getData() {
  const newArray = await iterateWithTimeout([1, 2, 3, 4, 5], 1000, x => x + 100);
  console.log(newArray); // 5 seconds later.. [ 101, 102, 103, 104, 105 ]
}

Optionally skipping over indexes at the start, it will not need to be called on the first 5 elements so it only takes 1 second, doesn't return the elements it skipped over.

async function getData() {
  const newArray = await iterateWithTimeout([0, 0, 0, 0, 0, 600], 1000, x => x + 100, 5);
  console.log(newArray); // 1 second later -> [ 700 ]
}

async function getData() {
  const array = [0, 0, 0, 0, 0];
  const newArray = await iterateWithTimeout([100, 200, 300, 400], 1000, x => x + 100, 0, array);

  console.log(newArray); // 4 seconds later -> [ 0, 0, 0, 0, 0, 200, 300, 400, 500 ]
  console.log(array); // [0,0,0,0,0], array is not mutated and we returned a new one.
}

Simplified by passing in variables to make it readable.

async function getData() {
  const array = [0, 0, 0, 0, 0];
  const input = [100, 200, 300, 400];
  const delay = 1000;
  const addFifty = x => x + 50;

  const newArray = await iterateWithTimeout(input, delay, addFifty, 0, array);

  console.log(newArray); // 4 seconds later -> [ 0, 0, 0, 0, 0, 150, 250, 350, 450 ]
  console.log(array); // [0,0,0,0,0], array is not mutated and we returned a new one.
}