ES6 Fiddle

Map Function

let doubles = [1,2,3,4].map(v => v+1);
console.log(doubles[0]); //2

let terms = ["Ben", "Den", "Sam"];
console.log(terms.map(name => `I am ${name}`));
// I am Ben, I am Den, I am Sam
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Arrow Function

let nums = [1,2,3,4,5,6];
let fives = [];

nums.forEach(v => {
   if (v % 5 === 0)
       fives.push(v)
})

console.log(fives);
// print 5
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Rest Parameter

function f (x, y, ...a) {
    return (x + y) * a.length;
}
console.log(f(1, 2, "hello", true, 7) === 9);
// returns true
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