src/throttle.js

/*
Rate limit a function call. Wait is the minimum number of milliseconds between calls.
If leading is true, the first call to the throttled function is immediately called.
If trailing is true, once the wait time has passed the function is called. 

This code is cribbed from https://github.com/jashkenas/underscore
*/
const throttle = function(func, wait, leading = true, trailing = true) {
	let timeout, context, args, result
	let previous = 0

	const later = function() {
		previous = leading === false ? 0 : Date.now()
		timeout = null
		result = func.apply(context, args)
		if (!timeout) context = args = null
	}

	const throttled = function() {
		const now = Date.now()
		if (!previous && leading === false) previous = now
		const remaining = wait - (now - previous)
		context = this
		args = arguments
		if (remaining <= 0 || remaining > wait) {
			if (timeout) {
				clearTimeout(timeout)
				timeout = null
			}
			previous = now
			result = func.apply(context, args)
			if (!timeout) context = args = null
		} else if (!timeout && trailing !== false) {
			timeout = setTimeout(later, remaining)
		}
		return result
	}

	throttled.cancel = function() {
		clearTimeout(timeout)
		previous = 0
		timeout = context = args = null
	}

	return throttled
}

const throttledConsoleLog = throttle(function(...params) {
	console.log(...params)
}, 1000)

export { throttle, throttledConsoleLog }