配列の分割代入
/**
* 配列の分割代入(ES6)
*/
//ES2015 before ---------------------------------------------
function arr1(){
var data = [56, 40, 26, 82];
document.getElementById('hoge1').textContent = data[0] + ', ' + data[1] + ', ' + data[2] + ', ' + data[3];
}
arr1();
//ES2015 after 分割代入---------------------------------------------
function arr2(){
let data = [57, 41, 27, 83];
let [x0, x1, x2, x3] = data;
document.getElementById('hoge2').textContent = x0 + ', ' + x1 + ', ' + x2 + ', ' + x3;
}
arr2();
//スプレッド(…)演算子を使うと残りの要素すべてまとめて配列として切り出せる
function arg3(){
let data = [4, 6, 9, 10, 20, 50];
let [x0, x1, ...oth] = data;
document.getElementById('hoge3').textContent = x0 + ', ' + x1 + ', ' + oth;
}
arg3();
