promises
// Creating a new promise
const myPromise = new Promise((resolve, reject) => {
// setTimeout(() => {
resolve('Promise resolved');
// }, 5000);
// reject(new Error("…")); // ignored
});
myPromise.then((value) => {
console.log(value);
// expected output: "promise resolved"
});
console.log(myPromise);
// expected output: [object Promise]....
....
// Creating a new promise
const myPromise = new Promise((resolve, reject) => {
reject('goomorning');
// setTimeout(() => {
// resolve('Promise resolved');
// }, 1000);
});
myPromise.then((v) => {
console.log(v);
// expected output: "promise resolved"
}).catch(err=>{
console.log(err);
});
console.log(myPromise);//pending
// expected output: [object Promise]
....
let promise = new Promise(function(resolve, reject) {
resolve('goodmorning');
setTimeout(() => reject(new Error("Whoops!")), 1000);
});
// reject runs the second function in .then
promise.then(
result => alert(result), // doesn't run
);
promise.catch(
error => alert(error) // shows "Error: Whoops!" after 1 second
);
....
async function f() {
let promise = new Promise((resolve, reject) => {
setTimeout(() => resolve("good afternoon"), 1000)
});
let result = await promise;
// wait until the promise resolves (*)
alert(result); // "done!"
}
f();
......
for(i=1;i<=4;i++){
setInterval(() => {
console.log(i);
}, i*1000);
}
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