What advanced feature does this implementation provide for async operations?
function createThrottledPromise(func, limit) {
let lastResolved = 0;
let pending = null;
return async function(...args) {
const now = Date.now();
if (now - lastResolved >= limit) {
lastResolved = now;
return func.apply(this, args);
}
if (!pending) {
pending = new Promise(resolve => {
setTimeout(async () => {
const result = await func.apply(this, args);
pending = null;
lastResolved = Date.now();
resolve(result);
}, limit - (now - lastResolved));
});
}
return pending;
};
}
This implementation provides advanced async operation handling: 1) It combines throttling with Promise-based operations, 2) It ensures only one pending Promise exists at a time, 3) It properly queues and throttles async function calls, 4) The implementation maintains proper timing even with async operations, 5) It prevents multiple in-flight requests during the throttle period, 6) The approach is particularly useful for API calls or async data operations, 7) It handles both immediate and delayed execution of async functions, 8) This pattern is valuable for rate-limiting async operations in modern applications.