debounce.js (1221B)
1 /* This Source Code Form is subject to the terms of the Mozilla Public 2 * License, v. 2.0. If a copy of the MPL was not distributed with this 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 4 5 "use strict"; 6 7 /** 8 * Create a debouncing function wrapper to only call the target function after a certain 9 * amount of time has passed without it being called. 10 * 11 * @param {Function} func 12 * The function to debounce 13 * @param {number} wait 14 * The wait period 15 * @param {object} scope 16 * The scope to use for func 17 * @return {Function} The debounced function, which has a `cancel` method that the 18 * consumer can call to cancel any pending setTimeout callback. 19 */ 20 exports.debounce = function (func, wait, scope) { 21 let timer = null; 22 23 function clearTimer(resetTimer = false) { 24 if (timer) { 25 clearTimeout(timer); 26 } 27 if (resetTimer) { 28 timer = null; 29 } 30 } 31 32 const debouncedFunction = function () { 33 clearTimer(); 34 35 const args = arguments; 36 timer = setTimeout(function () { 37 timer = null; 38 func.apply(scope, args); 39 }, wait); 40 }; 41 42 debouncedFunction.cancel = clearTimer.bind(null, true); 43 44 return debouncedFunction; 45 };