Flatten an Array!

README.md

Flatten an array.

Requirements

You will need node js to run this array flattener.

How to run

Open your terminal/cmd and execute:

npx https://gist.github.com/lrn2prgrm/e82a719b030ee422018461d21052f4a0

index.js

#!/usr/bin/env node

/* Returns a new array that is a flattened version of the param */
function flatten(array){
  const accumulatorArray = []
  return array.reduce(flattenReducer, accumulatorArray);
}

/* A recursive reducer that will push all the elements into the accumulator array */
function flattenReducer(array, e) {
  const eIsAnArray = e != null && e.constructor.name === 'Array';
  if (eIsAnArray) {
    e.reduce(flattenReducer, array);
  } else {
    array.push(e);
  }
  return array
}

function testFlatten(array, expectedArrayString) {
  console.log('try ' + JSON.stringify(array));
  console.log('flattening...');
  const newArray = JSON.stringify(flatten(array));
  if (newArray !== expectedArrayString) {
    throw Error('Expected ' + expectedArrayString + ' but recieved ' + newArray)
  }
  console.log(newArray);
}

testFlatten([[[[[[[1]]]]]]], "[1]")
testFlatten([[[[[[[1]]]]]],2], "[1,2]")
testFlatten([[1,2],3,4,[[[[5],6,[7],[[8,9]]]]]], "[1,2,3,4,5,6,7,8,9]")

package.json

{
  "name": "npx-flatten",
  "version": "0.0.1",
  "bin": "./index.js"
}