One Pager Cheat Sheet
Throttlingis a technique to limit the number of times a function can execute in any given interval, which is useful for cases likeinfinite scrollingwhere a function needs to be executed only once per user action.- By using a
booleanflag likeisThrottlingand thesetTimeoutmethod, we can create athrottlefunction that executes a given function after a certain amount of time, and save any further calls with different arguments for later invocation.
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}function throttle(func, waitTime) { // Set isThrottling flag to false to start // and savedArgs to null let isThrottling = false, savedArgs = null; // Spread the arguments for .apply return function (args) { // Return a wrapped function // Flag preventing immediate execution if (!isThrottling) { // Actual initial function execution func.apply(this, args); // Flip flag to throttling state isThrottling = true; // Queue up timer to flip the flag so future iterations can occur function queueTimer() { setTimeout(() => { // Stop throttling isThrottling = false; // Queueing up the next invocation after wait time passes if (savedArgs) { func.apply(this, savedArgs); isThrottling = true; savedArgs = null; queueTimer(); } }, waitTime); } queueTimer(); } // Wait state until timeout is done // Save argumentsOUTPUT
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