A blog about software by Alexander Yaäkov Garber.

Arrays in Javascript vs Ruby

js array map filter reduce

Published on 23 Dec 2022

Setup in Javascript

const array = [1, 2, 10, 16];
const double = [];
const newArray = array.forEach((num) => {
double.push(num * 2);
});

ary = [1, 2, 10, 16]
new_array = []
ary.each { |num| double << num * 2 }

const array = [1, 2, 10, 16];
const mapArray = array.map(num => num * 2);

array = [1, 2, 10, 16]
map_array = array.map { |num| num * 2 }

const array = [1, 2, 10, 16];
const filterArray = array.filter(num => num > 5);

array = [1, 2, 10, 16]
select_array = array.select { |num| num > 5 }

const array = [1, 2, 10, 16];
const reduceArray = array.reduce((accumulator, num) => {
  return accumulator + num
}, 0);
// 1 + 2 + 10 + 16
// 29

array = [1, 2, 10, 16]
reduce_array = array.reduce(0) { |accumulator, num| accumulator + num }
reduce_array = array.reduce(:+)