Javascript: passing in a dynamic array: returning multiple promises in a function - Stack Overflow

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I have a Javascript function that takes in an int argument and returns a promise. I also have an array of ints(variable length) and I would like to call my function multiple times passing in each int to it and return multiple promises in one function. How do I accomplish this? The closest I could find on SO was JS return multiple promises in one function

function myFunction(input)
{
    return Promise.resolve(input);
}

/*
function invokedFunction(input)
{
    return function myFunction() {return Promise.resolve(input);}
}
function waitForAll()
{
    var resultArray = [];
    resultArray = await callMyFunction();
}
*/

function callMyFunction(inputArray)
{
    Promise.all[myFunction(pass in each item from inputArray)..... ];


/*
    const promisesArray = [];
    if(Array.isArray(inputArray)){
        inputArray.forEach(function(item, index){
            promisesArray[index] = invokedFunction(item);                      
        });
    }
    return Promise.all(promisesArray);
*/
}

var inputArray = [1, 2, 3, 4, 5];
callMyFunction(inputArray);

I have a Javascript function that takes in an int argument and returns a promise. I also have an array of ints(variable length) and I would like to call my function multiple times passing in each int to it and return multiple promises in one function. How do I accomplish this? The closest I could find on SO was JS return multiple promises in one function

function myFunction(input)
{
    return Promise.resolve(input);
}

/*
function invokedFunction(input)
{
    return function myFunction() {return Promise.resolve(input);}
}
function waitForAll()
{
    var resultArray = [];
    resultArray = await callMyFunction();
}
*/

function callMyFunction(inputArray)
{
    Promise.all[myFunction(pass in each item from inputArray)..... ];


/*
    const promisesArray = [];
    if(Array.isArray(inputArray)){
        inputArray.forEach(function(item, index){
            promisesArray[index] = invokedFunction(item);                      
        });
    }
    return Promise.all(promisesArray);
*/
}

var inputArray = [1, 2, 3, 4, 5];
callMyFunction(inputArray);

• javascript
• promise

Share Improve this question Follow asked 36 mins ago SoftwareDveloperSoftwareDveloper 72033 gold badges88 silver badges3030 bronze badges 2

• What's wrong with the code you've commented out? Although a simpler way would be return Promise.all(inputArray.map(item => myFunction(item))) – Guy Incognito Commented 13 mins ago
• Use array.map() to call a function that returns a promise for each array element. – Barmar Commented 13 mins ago

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1 Answer 1

Sorted by: Reset to default 0

var inputArray = [1, 2, 3, 4, 5];

    function getPromiseArray() {

      // Can use a for...of instead of .map if preferred
       const promises = inputArray.map((item) => callMyFunction(item)); 
          return promises;
     }

Then if you want to await all promises

let results = await Promise.all(getPromiseArray())

Promise.all returns an array of the fulfillment values

---

A example function to just loop through the results

  async function processPromises() {
    try {
    // Wait for all promises to resolve
    const results = await Promise.all(getPromiseArray());

    // Log each result
    for (let result of results) {
      console.log(result);
    }
  } catch (error) {
    console.error("An error occurred while processing promises:", error);
  }
}

---

Note:

• When using promise.all, it’s worth noting that if any promise in the input array rejects, the whole Promise.all will reject.

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