How To Use: sort(), filter() keys() in JavaScript

readme.md

𝘀𝗼𝗿𝘁()

This method sorts the elements of an array in place and returns the sorted array. The default sort order is ascending, built upon converting the elements into strings and comparing their UTF-16 code unit values sequences.

𝗳𝗶𝗹𝘁𝗲𝗿()

This method creates a new array with all the elements that pass the test implemented by the provided function. It doesn't execute the function for array elements without values and doesn't change the original array.

𝗸𝗲𝘆𝘀()

This method returns a new array iterator that contains the keys for each index in the given input array.

filter.js

const isEven = (num) => num % 2 === 0;

const filtered = [9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20].filter(isEven);
console.log(filtered); // output: [10, 12, 14, 16, 18, 20]

keys.js

const array1 = ['x', 'y', 'z'];
const iterator1 = array1.keys();

for (const key of iterator1) {
  console.log(key);
} // outputs: 0, 1, 2

sort.js

const months = [
  'Jul',
  'Aug',
  'Sep',
  'Oct',
  'Mar',
  'Apr',
  'May',
  'Jun',
  'Nov',
  'Dec',
  'Jan',
  'Feb',
];
months.sort();
console.log(months); // output: [ 'Apr', 'Aug', 'Dec', 'Feb', 'Jan', 'Jul', 'Jun', 'Mar', 'May', 'Nov', 'Oct', 'Sep' ]

const numbers = [6, 4, 15, 10, 8];
numbers.sort((a, b) => a - b);
console.log(numbers); // output: [ 4, 6, 8, 10, 15 ]