Implement Debounce with Maximum Wait Time

Problem Statement

Standard debounce can potentially never execute if calls keep coming. In critical applications, we need a guarantee that the function will execute within a maximum time window. Implement a debounce with maxWait.

Requirements

Implement a debounce(func, wait, options) function where:

• maxWait (number) - maximum time the function can be delayed
• If maxWait is reached, function executes regardless of ongoing calls
• After maxWait execution, the cycle resets
• Standard debounce behavior applies within maxWait window

Example Usage

const sendAnalytics = (events) => {
  console.log(`Sending ${events.length} events at ${Date.now()}`);
};

// Debounce 100ms, but guarantee execution every 1 second
const debouncedAnalytics = debounce(sendAnalytics, 100, { maxWait: 1000 });

// Continuous stream of events (every 50ms for 3 seconds)
let events = [];
const interval = setInterval(() => {
  events.push({ type: "click", time: Date.now() });
  debouncedAnalytics(events);
}, 50);

// Without maxWait: nothing would execute during the 3 seconds
// With maxWait: executes at ~1000ms, ~2000ms, and ~3100ms (after interval stops)

setTimeout(() => clearInterval(interval), 3000);

Real-world Context

• Analytics event batching with SLA guarantees
• Real-time collaboration (periodic sync even during active editing)
• Progress indicators that must update within reasonable time

Follow-up Questions

1. How does this interact with leading/trailing options?
2. What's the relationship between wait and maxWait values?
3. How would you test the maxWait behavior?