174 lines
7.5 KiB
JavaScript
174 lines
7.5 KiB
JavaScript
|
(function (global, factory) {
|
||
|
|
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
|
||
|
|
typeof define === 'function' && define.amd ? define(['exports'], factory) :
|
||
|
|
(global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.throttleDebounce = {}));
|
||
|
|
})(this, (function (exports) { 'use strict';
|
||
|
|
|
||
|
|
/* eslint-disable no-undefined,no-param-reassign,no-shadow */
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Throttle execution of a function. Especially useful for rate limiting
|
||
|
|
* execution of handlers on events like resize and scroll.
|
||
|
|
*
|
||
|
|
* @param {number} delay - A zero-or-greater delay in milliseconds. For event callbacks, values around 100 or 250 (or even higher)
|
||
|
|
* are most useful.
|
||
|
|
* @param {Function} callback - A function to be executed after delay milliseconds. The `this` context and all arguments are passed through,
|
||
|
|
* as-is, to `callback` when the throttled-function is executed.
|
||
|
|
* @param {object} [options] - An object to configure options.
|
||
|
|
* @param {boolean} [options.noTrailing] - Optional, defaults to false. If noTrailing is true, callback will only execute every `delay` milliseconds
|
||
|
|
* while the throttled-function is being called. If noTrailing is false or unspecified, callback will be executed
|
||
|
|
* one final time after the last throttled-function call. (After the throttled-function has not been called for
|
||
|
|
* `delay` milliseconds, the internal counter is reset).
|
||
|
|
* @param {boolean} [options.noLeading] - Optional, defaults to false. If noLeading is false, the first throttled-function call will execute callback
|
||
|
|
* immediately. If noLeading is true, the first the callback execution will be skipped. It should be noted that
|
||
|
|
* callback will never executed if both noLeading = true and noTrailing = true.
|
||
|
|
* @param {boolean} [options.debounceMode] - If `debounceMode` is true (at begin), schedule `clear` to execute after `delay` ms. If `debounceMode` is
|
||
|
|
* false (at end), schedule `callback` to execute after `delay` ms.
|
||
|
|
*
|
||
|
|
* @returns {Function} A new, throttled, function.
|
||
|
|
*/
|
||
|
|
function throttle (delay, callback, options) {
|
||
|
|
var _ref = options || {},
|
||
|
|
_ref$noTrailing = _ref.noTrailing,
|
||
|
|
noTrailing = _ref$noTrailing === void 0 ? false : _ref$noTrailing,
|
||
|
|
_ref$noLeading = _ref.noLeading,
|
||
|
|
noLeading = _ref$noLeading === void 0 ? false : _ref$noLeading,
|
||
|
|
_ref$debounceMode = _ref.debounceMode,
|
||
|
|
debounceMode = _ref$debounceMode === void 0 ? undefined : _ref$debounceMode;
|
||
|
|
/*
|
||
|
|
* After wrapper has stopped being called, this timeout ensures that
|
||
|
|
* `callback` is executed at the proper times in `throttle` and `end`
|
||
|
|
* debounce modes.
|
||
|
|
*/
|
||
|
|
var timeoutID;
|
||
|
|
var cancelled = false;
|
||
|
|
|
||
|
|
// Keep track of the last time `callback` was executed.
|
||
|
|
var lastExec = 0;
|
||
|
|
|
||
|
|
// Function to clear existing timeout
|
||
|
|
function clearExistingTimeout() {
|
||
|
|
if (timeoutID) {
|
||
|
|
clearTimeout(timeoutID);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Function to cancel next exec
|
||
|
|
function cancel(options) {
|
||
|
|
var _ref2 = options || {},
|
||
|
|
_ref2$upcomingOnly = _ref2.upcomingOnly,
|
||
|
|
upcomingOnly = _ref2$upcomingOnly === void 0 ? false : _ref2$upcomingOnly;
|
||
|
|
clearExistingTimeout();
|
||
|
|
cancelled = !upcomingOnly;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The `wrapper` function encapsulates all of the throttling / debouncing
|
||
|
|
* functionality and when executed will limit the rate at which `callback`
|
||
|
|
* is executed.
|
||
|
|
*/
|
||
|
|
function wrapper() {
|
||
|
|
for (var _len = arguments.length, arguments_ = new Array(_len), _key = 0; _key < _len; _key++) {
|
||
|
|
arguments_[_key] = arguments[_key];
|
||
|
|
}
|
||
|
|
var self = this;
|
||
|
|
var elapsed = Date.now() - lastExec;
|
||
|
|
if (cancelled) {
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Execute `callback` and update the `lastExec` timestamp.
|
||
|
|
function exec() {
|
||
|
|
lastExec = Date.now();
|
||
|
|
callback.apply(self, arguments_);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* If `debounceMode` is true (at begin) this is used to clear the flag
|
||
|
|
* to allow future `callback` executions.
|
||
|
|
*/
|
||
|
|
function clear() {
|
||
|
|
timeoutID = undefined;
|
||
|
|
}
|
||
|
|
if (!noLeading && debounceMode && !timeoutID) {
|
||
|
|
/*
|
||
|
|
* Since `wrapper` is being called for the first time and
|
||
|
|
* `debounceMode` is true (at begin), execute `callback`
|
||
|
|
* and noLeading != true.
|
||
|
|
*/
|
||
|
|
exec();
|
||
|
|
}
|
||
|
|
clearExistingTimeout();
|
||
|
|
if (debounceMode === undefined && elapsed > delay) {
|
||
|
|
if (noLeading) {
|
||
|
|
/*
|
||
|
|
* In throttle mode with noLeading, if `delay` time has
|
||
|
|
* been exceeded, update `lastExec` and schedule `callback`
|
||
|
|
* to execute after `delay` ms.
|
||
|
|
*/
|
||
|
|
lastExec = Date.now();
|
||
|
|
if (!noTrailing) {
|
||
|
|
timeoutID = setTimeout(debounceMode ? clear : exec, delay);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
/*
|
||
|
|
* In throttle mode without noLeading, if `delay` time has been exceeded, execute
|
||
|
|
* `callback`.
|
||
|
|
*/
|
||
|
|
exec();
|
||
|
|
}
|
||
|
|
} else if (noTrailing !== true) {
|
||
|
|
/*
|
||
|
|
* In trailing throttle mode, since `delay` time has not been
|
||
|
|
* exceeded, schedule `callback` to execute `delay` ms after most
|
||
|
|
* recent execution.
|
||
|
|
*
|
||
|
|
* If `debounceMode` is true (at begin), schedule `clear` to execute
|
||
|
|
* after `delay` ms.
|
||
|
|
*
|
||
|
|
* If `debounceMode` is false (at end), schedule `callback` to
|
||
|
|
* execute after `delay` ms.
|
||
|
|
*/
|
||
|
|
timeoutID = setTimeout(debounceMode ? clear : exec, debounceMode === undefined ? delay - elapsed : delay);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
wrapper.cancel = cancel;
|
||
|
|
|
||
|
|
// Return the wrapper function.
|
||
|
|
return wrapper;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* eslint-disable no-undefined */
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Debounce execution of a function. Debouncing, unlike throttling,
|
||
|
|
* guarantees that a function is only executed a single time, either at the
|
||
|
|
* very beginning of a series of calls, or at the very end.
|
||
|
|
*
|
||
|
|
* @param {number} delay - A zero-or-greater delay in milliseconds. For event callbacks, values around 100 or 250 (or even higher) are most useful.
|
||
|
|
* @param {Function} callback - A function to be executed after delay milliseconds. The `this` context and all arguments are passed through, as-is,
|
||
|
|
* to `callback` when the debounced-function is executed.
|
||
|
|
* @param {object} [options] - An object to configure options.
|
||
|
|
* @param {boolean} [options.atBegin] - Optional, defaults to false. If atBegin is false or unspecified, callback will only be executed `delay` milliseconds
|
||
|
|
* after the last debounced-function call. If atBegin is true, callback will be executed only at the first debounced-function call.
|
||
|
|
* (After the throttled-function has not been called for `delay` milliseconds, the internal counter is reset).
|
||
|
|
*
|
||
|
|
* @returns {Function} A new, debounced function.
|
||
|
|
*/
|
||
|
|
function debounce (delay, callback, options) {
|
||
|
|
var _ref = options || {},
|
||
|
|
_ref$atBegin = _ref.atBegin,
|
||
|
|
atBegin = _ref$atBegin === void 0 ? false : _ref$atBegin;
|
||
|
|
return throttle(delay, callback, {
|
||
|
|
debounceMode: atBegin !== false
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
exports.debounce = debounce;
|
||
|
|
exports.throttle = throttle;
|
||
|
|
|
||
|
|
Object.defineProperty(exports, '__esModule', { value: true });
|
||
|
|
|
||
|
|
}));
|
||
|
|
//# sourceMappingURL=index.js.map
|