when reading Promise :
var promise1 = new Promise(function(resolve, reject) {
setTimeout(resolve, 100, "foo");
});if an error is thrown in the executor function, the promise state is rejected. The return value of the executor function is ignored.
how do you understand the return value of the executor function here?
isn"t Promise supposed to be resolve or reject to execute parameter passing? What is Promise"s executor ?
executor is the parameter of Promise is this anonymous function
these two sentences are to remind you
function(resolve, reject) {}How does the code return only the result after the last asynchronous operation in the for loop is completed as shown in the figure? Please stop by and give me a hand. ...
Source code see here Promise.prototype.then = function(onFulfilled, onRejected) { if (this.constructor !== Promise) { return safeThen(this, onFulfilled, onRejected); } var res = new Promise(noop); handle(this, new Handler(onFulfilled, onR...
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