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                // オブジェクトを引数として受けて、それを展開する書き方
// Propertyがvalueとnameのものを展開して、valueとnameで受ける
const testFunction = ({value,name}) => (value + name)

const testObject = {
	value: "a",
	name: "b",


const list =[0,1,2,3,4];
const list2 =["a","b","c"];

const addList = (list, list2) => {
	return [...list,...list2];


// slice(n)はn番目を含んでそれ以降の配列を返す
var newList = list.slice(2)

// slice(0,n)は0から、n番目を含まない、その範囲の配列を返す
var newList = list.slice(0,2)

// slice(m,n)はmから、n番目を含まない、その範囲の配列を返す
var newList = list.slice(1,2)

// index 番目(0から始まるやつで) の配列だけを削除するFn
const removeCounter = (list, index) => {
  // Old way:
  //return list
  //  .slice(0, index)
  //  .concat(list.slice(index + 1));

  // ES6 way:
  return [
    ...list.slice(0, index),
    ...list.slice(index + 1)