Detailed explanation is in ANSWERS-ENG.md.
Пошаговое решение в ANSWERS-RU.md.
- Question 1
console.log('start');
const promise1 = new Promise((resolve, reject) => {
console.log(1)
})
console.log('end');Answer
start, 1, end- Question 2
console.log('start');
const promise1 = new Promise((resolve, reject) => {
console.log(1)
resolve(2)
})
promise1.then(res => {
console.log(res)
})
console.log('end');Answer
start , 1 , end и 2- Question 3
console.log('start');
const promise1 = new Promise((resolve, reject) => {
console.log(1)
resolve(2)
console.log(3)
})
promise1.then(res => {
console.log(res)
})
console.log('end');Answer
start , 1 , 3 , end и 2- Question 4
console.log('start');
const promise1 = new Promise((resolve, reject) => {
console.log(1)
})
promise1.then(res => {
console.log(2)
})
console.log('end');Answer
start , 1 , end- Question 5
console.log('start')
const fn = () => (new Promise((resolve, reject) => {
console.log(1);
resolve('success')
}))
console.log('middle')
fn().then(res => {
console.log(res)
})
console.log('end')Answer
start , middle, 1 , end и success- Question 6
console.log('start')
Promise.resolve(1).then((res) => {
console.log(res)
})
Promise.resolve(2).then((res) => {
console.log(res)
})
console.log('end')Answer
start , end , 1 и 2- Question 7
console.log('start')
setTimeout(() => {
console.log('setTimeout')
})
Promise.resolve().then(() => {
console.log('resolve')
})
console.log('end')Answer
start , end , resolve и setTimeout- Question 8
const promise = new Promise((resolve, reject) => {
console.log(1);
setTimeout(() => {
console.log("timerStart");
resolve("success");
console.log("timerEnd");
}, 0);
console.log(2);
});
promise.then((res) => {
console.log(res);
});
console.log(4);Answer
1, 2, 4, timeStart, timeEnd, success- Question 9
const timer1 = setTimeout(() => {
console.log('timer1');
const promise1 = Promise.resolve().then(() => {
console.log('promise1')
})
}, 0)
const timer2 = setTimeout(() => {
console.log('timer2')
}, 0)Answer
timer1, promise1, timer2- Question 10
console.log('start');
const promise1 = Promise.resolve().then(() => {
console.log('promise1');
const timer2 = setTimeout(() => {
console.log('timer2')
}, 0)
});
const timer1 = setTimeout(() => {
console.log('timer1')
const promise2 = Promise.resolve().then(() => {
console.log('promise2')
})
}, 0)
console.log('end');Answer
start, end, promise1, timer1, promise2, timer2- Question 11
async function asyncFunc() {
console.log(2);
await Promise.resolve();
console.log(4);
}
console.log(1);
asyncFunc();
console.log(3);Answer
1, 2, 3, 4- Question 12
Promise.resolve(1)
.then(2)
.then(Promise.resolve(3))
.then(console.log);Answer
1- Question 13
console.log('first');
setTimeout(() => console.log('second'), 0);
new Promise((resolve, reject) => {
console.log('third');
resolve();
}).then(() => console.log('fourth'));
console.log('fifth');Answer
first, third, fifth, fourth, second- Question 14
setTimeout(() => console.log("1"), 0);
new Promise((resolve, reject) => {
console.log("2");
for (let i = 0; i < 10000; i++) {
if (i === 9999) resolve();
}
console.log("3");
}).then(() => console.log("4"));
console.log("5");Answer
2, 3, 5, 4, 1- Question 15
Promise.reject('error')
.then(res => console.log('success:', res), err => console.log('fail:', err))Answer
fail: error- Question 16
async function func() {
console.log(1);
await new Promise(resolve => setTimeout(resolve, 1000));
console.log(3)
}
console.log(2);
func();
console.log(4);Answer
2, 1, 4, 3- Question 17
Promise.resolve()
.then(() => {
console.log('then1');
Promise.resolve().then(() => console.log('then1.1'));
})
.then(() => console.log('then2'));Answer
then1, then1.1, then2- Question 18
setTimeout(() => console.log('a'), 0);
Promise.resolve().then(() => console.log('b')).then(() => console.log('c'));Answer
b, c, a- Question 19
console.log('start');
setTimeout(() => console.log('setTimeout'), 0);
Promise.resolve().then(() => console.log('promise'));
console.log('end');Answer
start, end, promise, setTimeout- Question 20
async function test() {
console.log(1);
await async function() { console.log(2) }();
console.log(3);
}
console.log(4);
test();
console.log(5);