After the child promise is resolved, have the parent function return a boolean value

Question

After the child promise is resolved, have the parent function return a boolean value

I am currently faced with a challenge in my framework where the parent function must output either true or

false>. However, I also need to perform an asynchronous operation within that function.</p>
<p>How can I ensure that the parent function returns <code>true

or false after completing the async task?

An example of what doesn't work is as follows:

   function parent() {
     const child = new Promise();
     child.then(
       function (success) { return true },
     )
   }

The issue here is that the return statement is inside the context of the child.then() function.

javascript asynchronous promise

Answer 1

Answer №1

To ensure smooth execution, it is essential that the parent function is also asynchronous. Failure to do so will result in blocking the main thread, which goes against best practices.

Follow this approach:

const parent = async () => {
    const childResponse = await child();
    if (childResponse === "something") {
        return true;
    } else {
        return false;
    }
};

Avoid doing this:

const parent = () => {
    let promiseResult, parentReturnValue;

    child.then(result => {
        promiseResult = result;
        if (promiseResult === "something") {
            parentReturnValue = true;
        } else {
            parentReturnValue = false;
        }
    });

    while (promiseResult === undefined) {
        // Main thread blocked
    }
    
    return parentReturnValue;
};

Answer 2

To ensure smooth execution, it is essential that the parent function is also asynchronous. Failure to do so will result in blocking the main thread, which goes against best practices.

Follow this approach:

const parent = async () => {
    const childResponse = await child();
    if (childResponse === "something") {
        return true;
    } else {
        return false;
    }
};

Avoid doing this:

const parent = () => {
    let promiseResult, parentReturnValue;

    child.then(result => {
        promiseResult = result;
        if (promiseResult === "something") {
            parentReturnValue = true;
        } else {
            parentReturnValue = false;
        }
    });

    while (promiseResult === undefined) {
        // Main thread blocked
    }
    
    return parentReturnValue;
};

After the child promise is resolved, have the parent function return a boolean value

Answer №1

Similar questions

Is there a simpler way to retrieve data from PHP or to efficiently filter the data once it's been retrieved?

Generate a fresh object if the values within the TypeScript object are identical

Emphasize any word starting with an @ symbol to highlight its importance

Learn how to eliminate all text characters from a string using jQuery, leaving only the numerical values behind

Unable to establish connection with server through Ajax request on HTML page

How can I retrieve a variable in a JavaScript AJAX POST request?

What could be causing my table to appear multiple times in the HTML when using jQuery?

Issue encountered with Ionic and Angular 2: Denied application of style from 'http://localhost:8100/build/main.css' due to unsupported MIME type ('text/html')

JSLint error: Inconsistent use of spaces and tabs detected

Plugin refresh after callback

Is there a way to position the menu above the button?

LeafletJS and ReactJS integration causing misalignment in tile ordering

Error message: The Bootstrap .dropdown() method failed because it encountered an "Uncaught TypeError: undefined is not a function"

Arranging Data in AngularJS based on Selected Filter Criteria

Use the npm-search feature to show only the name and description columns in the search results

Change the left position of the sliding menu in real-time

React ensures that the page is not rerendered until after data has been fetched

Unable to call an object that may be 'undefined': Utilizing a function with a return object that includes asynchronous functions as properties

Adding hyperlinks that do not redirect

What is causing the most recent iPhones to have issues with my Javascript code?