Remove empty or falsy elements

const array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];

// remove empty holes, preserve undefined and null
const filtered = array.filter(() => true);
// [0, 1, null, 2, '', 3, undefined, 3, 4, 4, 5, 6]

// remove falsy values based on Boolean constructor
const filtered2 = array.filter(Boolean);
// [1, 2, 3, 3, 4, 4, 5, 6]

Finding distinct elements

Distinct primitive elements

const elements = [1, 2, 2, 3, 4, 5, 5, 6];
const distinctElements = [...new Set(elements)]; // [1, 2, 3, 4, 5, 6];

Distinct object entry values

Callback can be passed into the

const objectArr = [
  {"name": "John", "age": 17},
  {"name": "Anny", "age": 24},
  {"name": "Paul", "age": 24},
];

const distinctObjectValues = [
  ...new Set(objectArr.map(x => x.age))
]; // [17, 24]

Get First Element of Array

// The simplest way to access the first element
array[0]

But this requires you to check if array[0] exists

The advantage of find() is its efficiency as it exits the loop when the first value satisfying the condition is reached

const first = array.find(Boolean)

// first element even if falsy
const first = array.find(() => true)

// can be falsy, but not null or undefined
const first = array.find(e => typeof e !== 'undefined')

Using destructuring

const [first] = [1,2,3];

Grab Random Index from Array