MENU


Promise.resolve() and Promise.reject()

The static function Promise.resolve(value) or Promise.reject(value) returns a promise that is resolved or rejected respectively, with the given value.


RESETRUNFULL
<!DOCTYPE html><html><body><script>

Promise.reject(100).then(
   console.log,
   n => {console.log(n*2)});  // 200

</script></body><html>

Passing a Promise object to Promise.resolve() is identical to calling the promise directly.


RESETRUNFULL
<!DOCTYPE html><html><body><script>

var p = new Promise(resolve=>{
   resolve(100);});console.log(Promise.resolve(p) === p); // truePromise.resolve(p).then(
   console.log,
   n => {console.log(n*2)});  // 100

</script></body><html>

Passing to Promise.resolve() a thenable (an object with a 'method' taking two callbacks) is identical to calling a promise with the two callbacks in the thenable.


RESETRUNFULL
<!DOCTYPE html><html><body><script>

var thenable =
        {then : (onFulfill, onReject) => {onFulfill('fulfilled');}};Promise.resolve(thenable).then(console.log);// fulfilledvar p = new Promise(resolve=>{resolve('fulfilled');});                                               //just identical to the abovep.then(console.log);// fulfilled

</script></body><html>