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Async Operations

Sharpen your skills in asynchronous programming by practicing the use of async/await, Promises, and callback functions. Dive into scenarios that require asynchronous operations, such as making API requests and delayed code execution.

All Practice Questions

Coding Format

Questions List

  • DebounceImplement a function to limit how many times a function can be executed by delaying the execution of the function until after a specified time after its last execution attempt
    Languages
    JSTS
  • Promise.allImplement the Promise.all() function that resolves to an array of results if all the input elements are resolved or rejects otherwise
    Languages
    JSTS
  • Traffic LightBuild a traffic light where the lights switch from green to yellow to red after predetermined intervals and loop indefinitely
    Available frameworks
  • Digital ClockBuild a 7-segment digital clock that shows the current time
    Available frameworks
  • Job BoardBuild a job board that displays the latest job postings from Hacker News
    Available frameworks
  • SleepImplement a function that pauses for a specified duration before resuming execution
    Languages
    JSTS
  • Cancellable IntervalImplement a function that acts like setInterval but returns a function to cancel the interval
    Languages
    JSTS
  • Cancellable TimeoutImplement a function that acts like setTimeout but returns a function to cancel the pending callback
    Languages
    JSTS
  • Promise.rejectImplement a function to return a Promise object rejected with a reason
    Languages
    JSTS
  • Promise.raceImplement the Promise.race() function that resolves or rejects when any of the input elements are resolved or rejected
    Languages
    JSTS
  • Progress BarsBuild a list of progress bars that fill up gradually when they are added to the page
    Available frameworks
  • Promise MergeImplement a function to merge the results of two promises into a single value
    Languages
    JSTS
  • Promise.resolveImplement a function to resolve a given value to a Promise
    Languages
    JSTS
  • Promise TimeoutImplement a function that resolves a promise if it is fulfilled within a timeout period and rejects otherwise
    Languages
    JSTS
  • PromisifyImplement a function that takes a function following the common error-first callback style and returns a version that returns promises
    Languages
    JSTS
  • Promisify IIImplement a promisify function that allows the original function to override the return value
    Languages
    JSTS
  • ThrottleImplement a function to control the execution of a function by limiting how many times it can execute over time
    Languages
    JSTS
  • Debounce IIImplement a debounce function that comes with a cancel method to cancel delayed invocations and a flush method to immediately invoke them
    Languages
    JSTS
  • Map AsyncImplement a function that maps an array of items with an asynchronous mapping function
    Languages
    JSTS
  • Promise.allSettledImplement the Promise.allSettled() function that resolves to an array of outcomes when all the input elements are either resolved or rejected
    Languages
    JSTS
  • Promise.anyImplement the Promise.any() function that resolves when any of the input elements are resolved
    Languages
    JSTS
  • Analog ClockBuild an analog clock where the hands update and move like a real clock
    Available frameworks
  • Grid LightsBuild a grid of lights where the lights deactivate in the reverse order they were activated
    Available frameworks
  • Like ButtonBuild a Like button that changes appearance based on the states
    Available frameworks
  • Progress Bars IIBuild a list of progress bars that fill up gradually in sequence, one at a time
    Available frameworks
  • Map Async LimitImplement a function that maps an array of items with an asynchronous mapping function while not exceeding the concurrency limit
    Languages
    JSTS
  • Progress Bars IIIBuild a list of progress bars that fill up gradually concurrently, up to a limit of 3
    Available frameworks
  • StopwatchBuild a stopwatch widget that can measure how much time has passed
    Available frameworks
  • Whack-A-MoleBuild a popular arcade game where players attempt to hit moles as they pop up from holes in a board
    Available frameworks
  • Progress Bars IVBuild a list of progress bars that fill up gradually concurrently, up to a limit of 3 and allows for pausing and resuming
    Available frameworks