Implement a Basic Throttle Function

Problem Statement

As a Staff Engineer reviewing production performance, I frequently encounter scenarios where we need to limit the rate of function execution—especially for high-frequency events. Implement a throttle utility that ensures a function executes at most once per specified time interval.

Requirements

Implement a throttle(func, wait) function that:

• Executes func immediately on the first call
• Ignores subsequent calls within the wait period
• After the wait period, the next call executes immediately
• Preserves this context and arguments

Example Usage

Key Difference from Debounce

Throttle	Debounce
Executes at regular intervals	Executes after activity stops
Guarantees execution during activity	Only executes when activity pauses
Use for: scroll, resize, mousemove	Use for: search input, form validation

Real-world Context

• Scroll event handlers for infinite scroll or parallax
• Mouse move handlers for drag operations
• Rate-limiting API calls
• Game loop input handling

Follow-up Questions

1. What happens to the last call if it falls within a throttle window?
2. How would you ensure the last call is always executed?