New fungsi di ES6

• .forEach() = Fungsi mirip seperti for biasa

• .map() = menghasilkan larik baru dari hasil suatu proses

• .filter() = menghasilkan larik baru hasil filter

check dokumentasi nya

Higher-Order Functions :: Eloquent JavaScript

Contoh foreach

//ES5
let numbers = [1,2,3];

for(let i = 0; i < angka.length; i++) {
    console.log(angka[i]);
}

//ES6
numbers.forEach(element => {
    console.log(element);
})

Latihan:

let numbers = [10,15,25];
 numbers.forEach(number => {
     console.log(number)
})
//hasil 10,15,25

// cara 1 map
let result = numbers.map(number => {
     return number*2;
})
console.log(result)
//hasil = 20, 30, 50

//cara 2 lebih sederhana
let result = numbers.map(number => number*2)
console.log(result)
//hasil = 20, 30, 50