zoryana94

const arr = [[1,2,[3]],4];

function flattenArray(arr = []) {
  let flattenedArray = [];

  arr.forEach(item => {
      if (Array.isArray(item)) {
          flattenedArray = [...flattenedArray, ...flattenArray(item)];
      } else {
          flattenedArray.push(item);

zoryana94

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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