TS Throttle function

gistfile1.txt

const throttleMap = new Map<Function, {throttledFunction: Function; args: any[]}>();

/**
 * Lets you call a function and have it throttled by a certain delay.
 * Useful for when a function may be spammed!
 *
 * @example
 * ```
 * function resize(w, h){
 *  console.log('resized', w, h);
 * }
 *
 * window.onResize = ()=>{
 *  throttle(resize, 100)(window.innerWidth, window.innerHeight);
 * }
 * ```
 *
 * @param fun the function you want throttled
 * @param delay how long until the function is executed
 */
export function throttle(fun: Function, delay = 100, scope?: any): Function
{
    if (!throttleMap.has(fun))
    {
        const throttledFunction = (...args): void =>
        {
            throttleMap.get(fun).args = args;

            setTimeout(() =>
            {
                const latestArgs = throttleMap.get(fun).args;

                if (scope)
                {
                    fun.call(scope, ...latestArgs);
                }
                else
                {
                    fun(...latestArgs);
                }
            }, delay);
        };

        throttleMap.set(fun, { throttledFunction, args: null });
    }

    return throttleMap.get(fun).throttledFunction;
}