throttle

throttle-simple-implementation.js

// Creates a throttled function that only invokes "originalFn" at most once per every "delayMs" milliseconds
function throttle(originalFn, delayMs) {
  let timeout; // timeout to keep track of the executions
  return (...args) => {
    if (timeout) { // if timeout is set, this is NOT the first execution, so ignore
      return;
    }
    
    // this is the first execution which we need to delay by "delayMs" milliseconds
    timeout = setTimeout(() => {
      originalFn(...args); // call the passed function with all arguments
      timeout = null; // reset timeout so that the subsequent call launches the process anew
    }, delayMs);
  }
}