Throttling is a technique used to control how many times we allow a function to be executed over time. When a JavaScript function is said to be throttled with a wait time of X milliseconds, it can only be invoked at most once every X milliseconds. The callback is invoked immediately and cannot be invoked again for the rest of the wait duration.

Implement a throttle function which accepts a callback function and a wait duration. Calling throttle() returns a function which throttled invocations of the callback function following the behavior described above.

Examples

let i = 0;
function increment() {
  i++;
}
const throttledIncrement = throttle(increment, 100);

// t = 0: Call throttledIncrement(). i is now 1.
throttledIncrement(); // i = 1

// t = 50: Call throttledIncrement() again.
//  i is still 1 because 100ms have not passed.
throttledIncrement(); // i = 1

// t = 101: Call throttledIncrement() again. i is now 2.
//  i can be incremented because it has been more than 100ms
//  since the last throttledIncrement() call at t = 0.
throttledIncrement(); // i = 2

Follow Up

• Throttle with cancel and leading/trailing options.

Reading

• Throttle on Lodash Documentation