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VisualizaçõesAwait inside a for loop inside an async function gives strange result
Can someone help explain to me why is it behave this way?
To the best of my knowledge, adding the await sleep(1) line should not affect the code flow in this case. However, it does.
function sleep(time) {
return new Promise((r) => setTimeout(r, time));
}
async function test(target) {
const ids = { a: ['a1', 'a2'], b: ['b3', 'b4'] }[target];
for (id of ids) {
console.log('X.', target, id);
// await sleep(1);
console.log('Y.', target, id);
}
}
test('a');
test('b');
Why?
Thanks!
·
Juan Pablo Isaza
2 Respostas
Responde à pergunta0
Try using for (const id of ids) {. Without const or let, you're defining id on the global scope.
function sleep(time) {
return new Promise((r) => setTimeout(r, time));
}
async function test(target) {
const ids = { a: ['a1', 'a2'], b: ['b3', 'b4'] }[target];
for (const id of ids) {
console.log('X.', target, id);
await sleep(1);
console.log('Y.', target, id);
}
}
test('a');
test('b');
·
Juan Pablo Isaza
Relatório
0
You're not waiting test('a') to finish.
When test('b') is reached, test('a') is still running (because it's an async function). If you want it to finish before starting the other one use .then():
test('a').then(()=>test('b'));
·
Juan Pablo Isaza
Relatório
Responde à pergunta