Published
Edited
Jan 27, 2020
{
var romeo = {name: "romeo", hasRose: false}
var juliet = {name: "jules", wantsRose: true}
if(romeo.hasRose===true){
romeo.hasRose=false
juliet.wantsRose=false
return "Happily ever after!"
}
else if(romeo.hasRose===false)
{
return "Romeo fails"
}
romeo.hasRose=true
}
{
var romeo = {name: "romeo", hasRose: false}
var juliet = {name: "jules", wantsRose: true}
if(romeo.hasRose===true){
romeo.hasRose=false
juliet.wantsRose=false
return "Happily ever after!"
}
else if(romeo.hasRose===false)
{
romeo.oweRose=true
juliet.wantsRose=false
}
romeo.hasRose=true
romeo.oweRose=false
romeo.hasRose=false
return "Happily ever after!"
}
promiseFunc = function() {
return new Promise(
function(resolve, reject) {
if(x % 2 === 0) {
return resolve(x)
}
else {
return reject(x)
}
}
)}
finalResult = (promiseFunc())
.then(x => x%3)
.then(x => x+30)
.catch(err => "I encountered an error: " + err + ". Sorry!")
{
var firstThing = 22
var secondThing = firstThing * 2 //note that the previous line has already finished executing before we get here
return secondThing
}
{
//don't worry about the syntax down here... Assume that all of the functions work
var cocktailList = axios.get('https://www.thecocktaildb.com/api/json/v1/1/filter.php?a=Non_Alcoholic')
var randomCocktailId = cocktailList.data.drinks[0].idDrink
var cocktail = axios.get('https://www.thecocktaildb.com/api/json/v1/1/lookup.php?i=' + randomCocktailId)
return cocktail
}
{
//don't worry about the syntax down here... Assume that all of the functions work
return axios.get('https://www.thecocktaildb.com/api/json/v1/1/filter.php?a=Non_Alcoholic')
.then(function(cocktailList) {
return cocktailList.data.drinks[0].idDrink
})
.then(function(randomCocktailId) {
return axios.get('https://www.thecocktaildb.com/api/json/v1/1/lookup.php?i=' + randomCocktailId)
.then(function(drink) {
return drink.data.drinks[0]
})
})
}
youPromiseToGiveMeFood = function (typeOfFood) {
return new Promise( function(s,f) {
return s(typeOfFood)}
)
}
iPromiseToPayYouBack = function(amt, from) {
return new Promise( function(s,f) {
return s(from - amt)}
)
}
eatFood = function(myStuff) {
return "I ate the " + myStuff.food
}
checkWhatIHave = function(myStuff) {
return "I have a " + myStuff.food + " and $" + myStuff.wallet + " dollars left."
}
// define the async function
promisedFoodTransaction = async function() {
var myFood;
var myWallet = 100;
// this will return a promise
myFood = youPromiseToGiveMeFood("Lakeview Beef w. Broccoli")
// then it'll keep executing down here
// this will also return a promise
myWallet = /* Promise */ iPromiseToPayYouBack(20, myWallet)
// the promises haven't been resolved, but I'm returning them anyway:
return {
food:myFood,
wallet: myWallet
}
}
promisedFoodTransaction() instanceof Promise
promisedFoodTransaction().then(eatFood)
promisedFoodTransaction().then(checkWhatIHave)
// define the async function
awaitFoodTransaction = async function() {
var myFood;
var myWallet = 100;
// the function will pause at this line below until you give me my food
myFood = await youPromiseToGiveMeFood("Lakeview Beef w. Broccoli")
// then it'll keep executing down here
// and pause until i pay you back
myWallet = await iPromiseToPayYouBack(20, myWallet)
// and now we've finished the transaction
// I return an object containing my belongings
return {
food:myFood,
wallet: myWallet
}
}
awaitFoodTransaction() instanceof Promise
awaitFoodTransaction().then(eatFood)
awaitFoodTransaction().then(checkWhatIHave)
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