Project import generated by Copybara.
GitOrigin-RevId: 63746295f1a5ab5a619056791995793d65529e62
diff --git a/node_modules/mdl-ext/es/utils/debounce-function.js b/node_modules/mdl-ext/es/utils/debounce-function.js
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+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+ value: true
+});
+
+var _apply = require("babel-runtime/core-js/reflect/apply");
+
+var _apply2 = _interopRequireDefault(_apply);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+/**
+ * Debouncing enforces that a function not be called again until a certain
+ * amount of time has passed without it being called.
+ *
+ * @see https://css-tricks.com/the-difference-between-throttling-and-debouncing/
+ * @see https://github.com/webmodules/raf-debounce
+ * @see https://github.com/moszeed/es6-promise-debounce
+ * @see https://gist.github.com/philbirnie/893950093611d5c1dff4246a572cfbeb/
+ * @see https://github.com/SliceMeNice-ES6/event-utils/blob/master/debounce.js
+ * @see https://github.com/jeromedecoster/raf-funcs
+ * @see http://unscriptable.com/2009/03/20/debouncing-javascript-methods/
+ * @see http://davidwalsh.name/javascript-debounce-function
+ *
+ * @param callback the callback
+ * @param threshold optional delay, default to 250 ms, min to 1000/60ms ms
+ * @param context optional context of this, default to global
+ * @return {Function} reference to immediate and cancel
+ */
+var MIN_THRESHOLD = 1000 / 60;
+
+var debounceFunction = function debounceFunction(callback) {
+ var threshold = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 250;
+ var context = arguments[2];
+
+
+ if (threshold < MIN_THRESHOLD) {
+ threshold = MIN_THRESHOLD;
+ }
+
+ if (!context) {
+ context = this || window;
+ }
+
+ var next = null;
+ var start = 0;
+
+ return function () {
+ for (var _len = arguments.length, args = Array(_len), _key = 0; _key < _len; _key++) {
+ args[_key] = arguments[_key];
+ }
+
+ var _cancel = function _cancel() {
+ if (next) {
+ window.cancelAnimationFrame(next);
+ next = null;
+ }
+ };
+
+ var execute = function execute() {
+ _cancel();
+ return (0, _apply2.default)(callback, context, args);
+ };
+
+ var later = function later() {
+ if (threshold - (Date.now() - start) <= 0) {
+ return execute();
+ }
+ next = window.requestAnimationFrame(later);
+ };
+
+ _cancel();
+ start = Date.now();
+ next = window.requestAnimationFrame(later);
+
+ return {
+ cancel: function cancel() {
+ return _cancel();
+ },
+ immediate: function immediate() {
+ return execute();
+ }
+ };
+ };
+};
+
+exports.default = debounceFunction;
+module.exports = exports["default"];
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