Destructuring #React 빠른 노트.

const cakeVarieties = ['Chocolate','KitKat','Mango', 'Brownie'];

const [myChoise1, myChoise2, ...rest] = cakeVarieties;

console.log(myChoise1); //Chocolate
console.log(myChoise2); //KitKat
console.log(rest); //['Mango','Brownie'] --Remember rest means other things left and which is only be declared at last position.

//Below is for #React.js

const premiumCakeVarieties = {sameNameHere1: 'Chocolate', sameNameHere2:'KitKat', sameNameHere3:{fruitCakes :['Mango','Pineaple']}, 
 sameNameHere4:'Brownie'};

const {sameNameHere1, sameNameHere2, sameNameHere4, sameNameHere3 : {fruitCakes:[cake1, cake2]}} = premiumCakeVarieties; //Notice: We have same variable name no matter in which order they are they will access array property where matching name of itself.

console.log(sameNameHere1); //Chocolate
console.log(sameNameHere2); //KitKat
console.log(sameNameHere4); //Brownie
console.log(sameNameHere3); //['Mango','Pineaple']
console.log(cake1); //Mango //this follows order here as we did not have key for it
console.log(cake2); //Pineaple //this follows order here as we did not have key for it

const [a, b, ...rest] = [1,2,3,4]; //here an array both sides.

const {a, b, ...rest} = obj; //here {} left side.