es6-promise

I would expect the code below to print one number on the console, then wait a second and then print another number. Instead, it prints all 10 numbers immediately and then waits ten seconds. What is the correct way to create a promise chain that behaves as described? function getProm(v) { return new Promise(resolve => { console.log(v); resolve(); }) } function Wait() { return new Promise(r => setTimeout(r, 1000)) } function createChain() { let a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]; let chain = Promise.resolve(); for (let i of a) { chain.then(()=>getProm(i)) .then(Wait) } return chain; }

I have a scenario where I am returning a promise. The promise basically give the response of a ajax request. On rejecting the promise it shows an error dialog that there is a server error. What I want to do is when the response code is 401, I neither want to resolve the promise nor reject it(cause it shows error dialog). I want to simply redirect to the login page. My code looks something like this function makeRequest(ur,params) { return new Promise(function(resolve,reject) { fetch(url,params) .then((response) => { let status = response.status; if (status >= 200 && status < 300) { response

Using ES6 promises, how do I create a promise without defining the logic for resolving it? Here's a basic example (some TypeScript): var promises = {}; function waitFor(key: string): Promise<any> { if (key in promises) { return promises[key]; } var promise = new Promise(resolve => { // But I don't want to try resolving anything here :( }); promises[key] = promise; return promise; } function resolveWith(key: string, value: any): void { promises[key].resolve(value); // Not valid :( } It's easily done with other promise libraries. JQuery's for example: var deferreds = {}; function waitFor(key:

With regard to these great two sources: NZakas - Returning Promises in Promise Chains and MDN Promises , I would like to ask the following: Each time that we return a value from a promise fulfillment handler, how is that value passed to the new promise returned from that same handler? For instance, let p1 = new Promise(function(resolve, reject) { resolve(42); }); let p2 = new Promise(function(resolve, reject) { resolve(43); }); let p3 = p1.then(function(value) { // first fulfillment handler console.log(value); // 42 return p2; }); p3.then(function(value) { // second fulfillment handler console

As I understand a promise is something that can resolve() or reject() but I was suprised to find out that code in the promise continues to execute after a resolve or reject is called. I considered resolve or reject being an async-friendly version of exit or return , that would halt all immediate function execution. Can someone explain the thought behind why the following example sometimes shows the console.log after a resolve call: var call = function() { return new Promise(function(resolve, reject) { resolve(); console.log("Doing more stuff, should not be visible after a resolve!"); }); };

I am looking for something similar to Promise.all that will continue to resolve promises concurrently even in the event that one or more of the promises reject or throw an error. Each request does not rely on another request. Close to what I want - please see comments function fetchRequest (request) { return new Promise(function (resolve, reject) { fetch(request) .then(function(response) { return response.text(); }).then(function (responseXML) { //Do something here. Maybe add data to dom resolve(responseXML); }).catch(function (err) { reject(new Error(err)); } } function promiseRequests

I have an API calling function that I would like to return the response.json() content as well as the response.status together in a single object. Like so: const getData = data => { return fetch('/api_endpoint',{ method: 'GET', headers: { 'Content-type': 'application/json' } }) .then(response => { return { body: response.json(), status: response.status } }) } The trouble is that response.json() is a promise, so I can't pull it's value until it's resolved. I can hack around it by doing this: const getData = data => { let statusRes = undefined; return fetch('/api_endpoint',{ method: 'GET',

JavaScript/Promise experts, I hope you can help me, because I don't understand how I can create a function that returns an existing promise instead of a new promise. I have done a lot of research, but all examples return a new promise every time the function is called. Assume I have a function that takes some time to process and generates a different result every time it is being called. When I use the new promise method then I still need to wait to complete every time and I don't get the same value if I recall the function. I have included proof of concept I have created that works as desired