Javascript ES6 Example - Arrows

//ES6 Arrows Example.

let evens = [0,2,4,6,8,10,12,14,16,18,20];
let odds = evens.map(v => v + 1);
let nums = evens.map((v,i) => v + i);
let pairs = evens.map(v => ({even: v , odd : v + 1}));
document.write(odds + '<br/>');
document.write(nums + '<br/>');
document.write(JSON.stringify(pairs) + '<br/>');

let fives = [];
nums.forEach(v => {
    if(v % 5 === 0){
        fives.push(v);
    }
});
document.write(JSON.stringify(fives) + '<br/>');

let eat_talk = {
    name : "최나나",
    word : ['라면','빵','냉면'],
    print_wrap(){
        this.word.forEach( f =>
            document.write(this.name + '는 '+ f + '를 먹었다.<br/> ')
        );
//          this.word.forEach(function(f){
//                  document.write(this.name + '는 '+ f + '를 먹었다.<br/> ')
//              }
//          );
    }




};
eat_talk.print_wrap();


let lets_play_dog = {
    pet : "댕댕이",
    eat: ['사료','간식','풀을 뜯고'],
    play : ['수영' , '산책' , '쟁반던지기'],
    print_eat(){
        this.eat.forEach( e => document.write(this.pet + '가 ' + e + ' 먹고있다.<br/> ')
        );
    },
    print_play(){
        this.play.forEach( p => document.write('난 오늘 ' + this.pet + '와 ' + p + '를 했다. <br/>'))
    }
};

lets_play_dog.print_eat();
lets_play_dog.print_play();