What does the following code return/print?
let facts = {numPlanets: 8, yearNeptuneDiscovered: 1846};
let {numPlanets, yearNeptuneDiscovered} = facts;
console.log(numPlanets); // 8
console.log(yearNeptuneDiscovered); // 1846
What does the following code return/print?
let planetFacts = {
numPlanets: 8,
yearNeptuneDiscovered: 1846,
yearMarsDiscovered: 1659
};
let {numPlanets, ...discoveryYears} = planetFacts;
console.log(discoveryYears);
// {yearNeptuneDiscovered: 1846, yearMarsDiscovered: 1659}
What does the following code return/print?
function getUserData({firstName, favoriteColor="green"}){
return `Your name is ${firstName} and you like ${favoriteColor}`;
}
getUserData({firstName: "Alejandro", favoriteColor: "purple"})
// Your name is Alejandro and you like purple
getUserData({firstName: "Melissa"})
// Your name is Melissa and you like green
getUserData({})
// Your name is undefined and you like green
What does the following code return/print?
let [first, second, third] = ["Maya", "Marisa", "Chi"];
console.log(first); // Maya
console.log(second); // Marisa
console.log(third); // Chi
What does the following code return/print?
let [raindrops, whiskers, ...aFewOfMyFavoriteThings] = [
"Raindrops on roses",
"whiskers on kittens",
"Bright copper kettles",
"warm woolen mittens",
"Brown paper packages tied up with strings"
]
console.log(raindrops); // "Raindrops on roses"
console.log(whiskers); // "whiskers on kittens"
console.log(aFewOfMyFavoriteThings);
// ["Bright copper kettles", "warm woolen mittens", "Brown paper packages tied up with strings"]
What does the following code return/print?
let numbers = [10, 20, 30];
[numbers[1], numbers[2]] = [numbers[2], numbers[1]]
console.log(numbers) // [10,30,20]
In this exercise, you’ll refactor some ES5 code into ES2015.
var obj = {
numbers: {
a: 1,
b: 2
}
};
var a = obj.numbers.a;
var b = obj.numbers.b;
/* Write an ES2015 Version */
const obj = {
numbers: {
a: 1,
b: 2
}
};
const {a,b} = obj.numbers
var arr = [1, 2];
var temp = arr[0];
arr[0] = arr[1];
arr[1] = temp;
[arr[0], arr[1]] = [arr[1], arr[0]]
Write a function called raceResults which accepts a single array argument. It should return an object with the keys first, second, third, and rest.
- first: the first element in the array
- second: the second element in the array
- third: the third element in the array
- rest: all other elements in the array
raceResults(['Tom', 'Margaret', 'Allison', 'David', 'Pierre'])
// {first: "Tom", second: "Margaret", third: "Allison", rest: ["David", "Pierre"]}
const raceResults = ([first, second, third, ...rest]) => ({first, second, third, rest})