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diff --git a/prototypes/promifill.js b/prototypes/promifill.js
new file mode 100644
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--- /dev/null
+++ b/prototypes/promifill.js
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+"use strict";
+
+function _createForOfIteratorHelper(o, allowArrayLike) { var it; if (typeof Symbol === "undefined" || o[Symbol.iterator] == null) { if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") { if (it) o = it; var i = 0; var F = function F() {}; return { s: F, n: function n() { if (i >= o.length) return { done: true }; return { done: false, value: o[i++] }; }, e: function e(_e) { throw _e; }, f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } var normalCompletion = true, didErr = false, err; return { s: function s() { it = o[Symbol.iterator](); }, n: function n() { var step = it.next(); normalCompletion = step.done; return step; }, e: function e(_e2) { didErr = true; err = _e2; }, f: function f() { try { if (!normalCompletion && it.return != null) it.return(); } finally { if (didErr) throw err; } } }; }
+
+function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
+
+function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
+
+function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
+
+var PENDING = void 0,
+ FULFILLED = true,
+ REJECTED = false;
+
+var Promifill = /*#__PURE__*/function () {
+ _createClass(Promifill, [{
+ key: "state",
+ get: function get() {
+ return PENDING;
+ }
+ }, {
+ key: "value",
+ get: function get() {
+ return void 0;
+ }
+ }, {
+ key: "settled",
+ get: function get() {
+ return false;
+ }
+ }]);
+
+ function Promifill(executor) {
+ var _this = this;
+
+ _classCallCheck(this, Promifill);
+
+ if (typeof executor != "function") {
+ throw new TypeError("Promise resolver ".concat(Object.prototype.toString.call(executor), " is not a function"));
+ }
+
+ defineProperty(this, "chain", []);
+ defineProperty(this, "observers", []);
+ var secret = [];
+
+ var resolve = function resolve(value, bypassKey) {
+ if (_this.settled && bypassKey !== secret) {
+ return;
+ }
+
+ defineProperty(_this, "settled", true);
+ var then_ = value && value.then;
+ var thenable = typeof then_ == "function";
+
+ if (thenable) {
+ defineProperty(value, "preventThrow", true);
+ }
+
+ if (thenable && value.state === PENDING) {
+ then_.call(value, function (v) {
+ return resolve(v, secret);
+ }, function (r) {
+ return reject(r, secret);
+ });
+ } else {
+ defineProperty(_this, "value", thenable ? value.value : value);
+ defineProperty(_this, "state", thenable ? value.state : FULFILLED);
+ schedule(_this.observers.map(function (observer) {
+ return {
+ handler: _this.state === FULFILLED ? observer.onfulfill : observer.onreject,
+ value: _this.value
+ };
+ }));
+
+ if (_this.state === REJECTED) {
+ raiseUnhandledPromiseRejectionException(_this.value, _this);
+ }
+ }
+ };
+
+ var reject = function reject(reason, bypassKey) {
+ if (_this.settled && bypassKey !== secret) {
+ return;
+ }
+
+ defineProperty(_this, "settled", true);
+ defineProperty(_this, "value", reason);
+ defineProperty(_this, "state", REJECTED);
+ schedule(_this.observers.map(function (observer) {
+ return {
+ handler: observer.onreject,
+ value: _this.value
+ };
+ }));
+ raiseUnhandledPromiseRejectionException(_this.value, _this);
+ };
+
+ try {
+ executor(resolve, reject);
+ } catch (error) {
+ reject(error);
+ }
+ }
+
+ _createClass(Promifill, [{
+ key: "then",
+ value: function then(onfulfill, onreject) {
+ var _this2 = this;
+
+ var chainedPromise = new this.constructor(function (resolve, reject) {
+ var internalOnfulfill = function internalOnfulfill(value) {
+ try {
+ resolve(typeof onfulfill == "function" ? onfulfill(value) : value);
+ } catch (error) {
+ reject(error);
+ }
+ };
+
+ var internalOnreject = function internalOnreject(reason) {
+ try {
+ if (typeof onreject == "function") {
+ resolve(onreject(reason));
+ } else {
+ reject(reason);
+ }
+ } catch (error) {
+ reject(error);
+ }
+ };
+
+ if (_this2.state === PENDING) {
+ _this2.observers.push({
+ onfulfill: internalOnfulfill,
+ onreject: internalOnreject
+ });
+ } else {
+ schedule([{
+ handler: _this2.state === FULFILLED ? internalOnfulfill : internalOnreject,
+ value: _this2.value
+ }]);
+ }
+ });
+ this.chain.push(chainedPromise);
+ return chainedPromise;
+ }
+ }, {
+ key: "catch",
+ value: function _catch(onreject) {
+ return this.then(null, onreject);
+ }
+ }, {
+ key: "finally",
+ value: function _finally(oncomplete) {
+ var _this3 = this;
+
+ var chainedPromise = new this.constructor(function (resolve, reject) {
+ var internalOncomplete = function internalOncomplete() {
+ try {
+ oncomplete();
+
+ if (_this3.state === FULFILLED) {
+ resolve(_this3.value);
+ } else {
+ reject(_this3.value);
+ }
+ } catch (error) {
+ reject(error);
+ }
+ };
+
+ if (_this3.state === PENDING) {
+ _this3.observers.push({
+ onfulfill: internalOncomplete,
+ onreject: internalOncomplete
+ });
+ } else {
+ schedule([{
+ handler: internalOncomplete
+ }]);
+ }
+ });
+ this.chain.push(chainedPromise);
+ return chainedPromise;
+ }
+ }], [{
+ key: "resolve",
+ value: function resolve(value) {
+ return value && value.constructor === Promifill ? value : new Promifill(function (resolve) {
+ resolve(value);
+ });
+ }
+ }, {
+ key: "reject",
+ value: function reject(reason) {
+ return new Promifill(function (_, reject) {
+ reject(reason);
+ });
+ }
+ }, {
+ key: "all",
+ value: function all(iterable) {
+ return new Promifill(function (resolve, reject) {
+ validateIterable(iterable);
+ var iterableSize = 0;
+ var values = [];
+
+ if (isEmptyIterable(iterable)) {
+ return resolve(values);
+ }
+
+ var add = function add(value, index) {
+ values[index] = value;
+
+ if (values.filter(function () {
+ return true;
+ }).length === iterableSize) {
+ resolve(values);
+ }
+ };
+
+ var _iterator = _createForOfIteratorHelper(iterable),
+ _step;
+
+ try {
+ for (_iterator.s(); !(_step = _iterator.n()).done;) {
+ var item = _step.value;
+
+ (function (entry, index) {
+ Promifill.resolve(entry).then(function (value) {
+ return add(value, index);
+ }, reject);
+ })(item, iterableSize++);
+ }
+ } catch (err) {
+ _iterator.e(err);
+ } finally {
+ _iterator.f();
+ }
+ });
+ }
+ }, {
+ key: "race",
+ value: function race(iterable) {
+ return new Promifill(function (resolve, reject) {
+ validateIterable(iterable);
+
+ if (isEmptyIterable(iterable)) {
+ return;
+ }
+
+ var _iterator2 = _createForOfIteratorHelper(iterable),
+ _step2;
+
+ try {
+ for (_iterator2.s(); !(_step2 = _iterator2.n()).done;) {
+ var entry = _step2.value;
+ Promifill.resolve(entry).then(resolve, reject);
+ }
+ } catch (err) {
+ _iterator2.e(err);
+ } finally {
+ _iterator2.f();
+ }
+ });
+ }
+ }]);
+
+ return Promifill;
+}();
+
+var defineProperty = function defineProperty(obj, propName, propValue) {
+ Object.defineProperty(obj, propName, {
+ value: propValue
+ });
+};
+
+var defer = function defer(handler) {
+ return function () {
+ for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
+ args[_key] = arguments[_key];
+ }
+
+ setTimeout.apply(void 0, [handler, 0].concat(args));
+ };
+};
+
+var thrower = function thrower(error) {
+ throw error instanceof Error ? error : new Error(error);
+};
+
+var raiseUnhandledPromiseRejectionException = defer(function (error, promise) {
+ if (promise.preventThrow || promise.chain.length > 0) {
+ return;
+ }
+
+ thrower(error);
+});
+
+var MutationObserverStrategy = /*#__PURE__*/function () {
+ function MutationObserverStrategy(handler) {
+ _classCallCheck(this, MutationObserverStrategy);
+
+ var observer = new MutationObserver(handler);
+ var node = this.node = document.createTextNode("");
+ observer.observe(node, {
+ characterData: true
+ });
+ }
+
+ _createClass(MutationObserverStrategy, [{
+ key: "trigger",
+ value: function trigger() {
+ this.node.data = this.node.data === 1 ? 0 : 1;
+ }
+ }]);
+
+ return MutationObserverStrategy;
+}();
+
+var NextTickStrategy = /*#__PURE__*/function () {
+ function NextTickStrategy(handler) {
+ _classCallCheck(this, NextTickStrategy);
+
+ this.scheduleNextTick = function () {
+ return process.nextTick(handler);
+ };
+ }
+
+ _createClass(NextTickStrategy, [{
+ key: "trigger",
+ value: function trigger() {
+ this.scheduleNextTick();
+ }
+ }]);
+
+ return NextTickStrategy;
+}();
+
+var BetterThanNothingStrategy = /*#__PURE__*/function () {
+ function BetterThanNothingStrategy(handler) {
+ _classCallCheck(this, BetterThanNothingStrategy);
+
+ this.scheduleAsap = function () {
+ return setTimeout(handler, 0);
+ };
+ }
+
+ _createClass(BetterThanNothingStrategy, [{
+ key: "trigger",
+ value: function trigger() {
+ this.scheduleAsap();
+ }
+ }]);
+
+ return BetterThanNothingStrategy;
+}();
+
+var getStrategy = function getStrategy() {
+ if (typeof window != "undefined" && typeof window.MutationObserver == "function") {
+ return MutationObserverStrategy;
+ }
+
+ if (typeof global != "undefined" && typeof process != "undefined" && typeof process.nextTick == "function") {
+ return NextTickStrategy;
+ }
+
+ return BetterThanNothingStrategy;
+};
+
+var schedule = function () {
+ var microtasks = [];
+
+ var run = function run() {
+ var handler, value;
+
+ while (microtasks.length > 0 && (_microtasks$shift = microtasks.shift(), handler = _microtasks$shift.handler, value = _microtasks$shift.value, _microtasks$shift)) {
+ var _microtasks$shift;
+
+ handler(value);
+ }
+ };
+
+ var Strategy = getStrategy();
+ var ctrl = new Strategy(run);
+ return function (observers) {
+ if (observers.length == 0) {
+ return;
+ }
+
+ microtasks = microtasks.concat(observers);
+ observers.length = 0;
+ ctrl.trigger();
+ };
+}();
+
+var isIterable = function isIterable(subject) {
+ return subject != null && typeof subject[Symbol.iterator] == "function";
+};
+
+var validateIterable = function validateIterable(subject) {
+ if (isIterable(subject)) {
+ return;
+ }
+
+ throw new TypeError("Cannot read property 'Symbol(Symbol.iterator)' of ".concat(Object.prototype.toString.call(subject), "."));
+};
+
+var isEmptyIterable = function isEmptyIterable(subject) {
+ var _iterator3 = _createForOfIteratorHelper(subject),
+ _step3;
+
+ try {
+ for (_iterator3.s(); !(_step3 = _iterator3.n()).done;) {
+ var _ = _step3.value;
+ // eslint-disable-line no-unused-vars
+ return false;
+ }
+ } catch (err) {
+ _iterator3.e(err);
+ } finally {
+ _iterator3.f();
+ }
+
+ return true;
+};
+
+//if (!window.Promise) {
+ window.Promise = Promifill;
+//}