mirror of
https://github.com/db48x/emularity.git
synced 2026-07-28 04:07:11 +00:00
960 lines
28 KiB
JavaScript
960 lines
28 KiB
JavaScript
/*!
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* @overview es6-promise - a tiny implementation of Promises/A+.
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* @copyright Copyright (c) 2014 Yehuda Katz, Tom Dale, Stefan Penner and contributors (Conversion to ES6 API by Jake Archibald)
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* @license Licensed under MIT license
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* See https://raw.githubusercontent.com/jakearchibald/es6-promise/master/LICENSE
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* @version 2.0.0
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*/
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(function() {
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"use strict";
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function $$utils$$objectOrFunction(x) {
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return typeof x === 'function' || (typeof x === 'object' && x !== null);
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}
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function $$utils$$isFunction(x) {
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return typeof x === 'function';
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}
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function $$utils$$isMaybeThenable(x) {
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return typeof x === 'object' && x !== null;
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}
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var $$utils$$_isArray;
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if (!Array.isArray) {
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$$utils$$_isArray = function (x) {
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return Object.prototype.toString.call(x) === '[object Array]';
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};
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} else {
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$$utils$$_isArray = Array.isArray;
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}
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var $$utils$$isArray = $$utils$$_isArray;
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var $$utils$$now = Date.now || function() { return new Date().getTime(); };
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function $$utils$$F() { }
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var $$utils$$o_create = (Object.create || function (o) {
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if (arguments.length > 1) {
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throw new Error('Second argument not supported');
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}
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if (typeof o !== 'object') {
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throw new TypeError('Argument must be an object');
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}
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$$utils$$F.prototype = o;
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return new $$utils$$F();
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});
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var $$asap$$len = 0;
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var $$asap$$default = function asap(callback, arg) {
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$$asap$$queue[$$asap$$len] = callback;
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$$asap$$queue[$$asap$$len + 1] = arg;
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$$asap$$len += 2;
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if ($$asap$$len === 2) {
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// If len is 1, that means that we need to schedule an async flush.
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// If additional callbacks are queued before the queue is flushed, they
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// will be processed by this flush that we are scheduling.
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$$asap$$scheduleFlush();
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}
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};
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var $$asap$$browserGlobal = (typeof window !== 'undefined') ? window : {};
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var $$asap$$BrowserMutationObserver = $$asap$$browserGlobal.MutationObserver || $$asap$$browserGlobal.WebKitMutationObserver;
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// test for web worker but not in IE10
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var $$asap$$isWorker = typeof Uint8ClampedArray !== 'undefined' &&
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typeof importScripts !== 'undefined' &&
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typeof MessageChannel !== 'undefined';
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// node
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function $$asap$$useNextTick() {
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return function() {
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process.nextTick($$asap$$flush);
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};
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}
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function $$asap$$useMutationObserver() {
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var iterations = 0;
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var observer = new $$asap$$BrowserMutationObserver($$asap$$flush);
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var node = document.createTextNode('');
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observer.observe(node, { characterData: true });
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return function() {
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node.data = (iterations = ++iterations % 2);
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};
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}
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// web worker
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function $$asap$$useMessageChannel() {
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var channel = new MessageChannel();
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channel.port1.onmessage = $$asap$$flush;
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return function () {
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channel.port2.postMessage(0);
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};
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}
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function $$asap$$useSetTimeout() {
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return function() {
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setTimeout($$asap$$flush, 1);
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};
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}
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var $$asap$$queue = new Array(1000);
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function $$asap$$flush() {
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for (var i = 0; i < $$asap$$len; i+=2) {
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var callback = $$asap$$queue[i];
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var arg = $$asap$$queue[i+1];
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callback(arg);
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$$asap$$queue[i] = undefined;
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$$asap$$queue[i+1] = undefined;
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}
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$$asap$$len = 0;
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}
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var $$asap$$scheduleFlush;
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// Decide what async method to use to triggering processing of queued callbacks:
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if (typeof process !== 'undefined' && {}.toString.call(process) === '[object process]') {
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$$asap$$scheduleFlush = $$asap$$useNextTick();
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} else if ($$asap$$BrowserMutationObserver) {
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$$asap$$scheduleFlush = $$asap$$useMutationObserver();
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} else if ($$asap$$isWorker) {
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$$asap$$scheduleFlush = $$asap$$useMessageChannel();
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} else {
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$$asap$$scheduleFlush = $$asap$$useSetTimeout();
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}
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function $$$internal$$noop() {}
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var $$$internal$$PENDING = void 0;
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var $$$internal$$FULFILLED = 1;
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var $$$internal$$REJECTED = 2;
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var $$$internal$$GET_THEN_ERROR = new $$$internal$$ErrorObject();
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function $$$internal$$selfFullfillment() {
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return new TypeError("You cannot resolve a promise with itself");
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}
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function $$$internal$$cannotReturnOwn() {
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return new TypeError('A promises callback cannot return that same promise.')
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}
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function $$$internal$$getThen(promise) {
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try {
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return promise.then;
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} catch(error) {
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$$$internal$$GET_THEN_ERROR.error = error;
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return $$$internal$$GET_THEN_ERROR;
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}
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}
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function $$$internal$$tryThen(then, value, fulfillmentHandler, rejectionHandler) {
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try {
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then.call(value, fulfillmentHandler, rejectionHandler);
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} catch(e) {
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return e;
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}
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}
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function $$$internal$$handleForeignThenable(promise, thenable, then) {
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$$asap$$default(function(promise) {
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var sealed = false;
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var error = $$$internal$$tryThen(then, thenable, function(value) {
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if (sealed) { return; }
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sealed = true;
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if (thenable !== value) {
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$$$internal$$resolve(promise, value);
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} else {
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$$$internal$$fulfill(promise, value);
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}
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}, function(reason) {
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if (sealed) { return; }
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sealed = true;
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$$$internal$$reject(promise, reason);
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}, 'Settle: ' + (promise._label || ' unknown promise'));
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if (!sealed && error) {
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sealed = true;
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$$$internal$$reject(promise, error);
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}
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}, promise);
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}
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function $$$internal$$handleOwnThenable(promise, thenable) {
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if (thenable._state === $$$internal$$FULFILLED) {
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$$$internal$$fulfill(promise, thenable._result);
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} else if (promise._state === $$$internal$$REJECTED) {
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$$$internal$$reject(promise, thenable._result);
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} else {
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$$$internal$$subscribe(thenable, undefined, function(value) {
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$$$internal$$resolve(promise, value);
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}, function(reason) {
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$$$internal$$reject(promise, reason);
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});
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}
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}
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function $$$internal$$handleMaybeThenable(promise, maybeThenable) {
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if (maybeThenable.constructor === promise.constructor) {
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$$$internal$$handleOwnThenable(promise, maybeThenable);
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} else {
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var then = $$$internal$$getThen(maybeThenable);
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if (then === $$$internal$$GET_THEN_ERROR) {
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$$$internal$$reject(promise, $$$internal$$GET_THEN_ERROR.error);
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} else if (then === undefined) {
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$$$internal$$fulfill(promise, maybeThenable);
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} else if ($$utils$$isFunction(then)) {
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$$$internal$$handleForeignThenable(promise, maybeThenable, then);
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} else {
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$$$internal$$fulfill(promise, maybeThenable);
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}
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}
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}
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function $$$internal$$resolve(promise, value) {
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if (promise === value) {
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$$$internal$$reject(promise, $$$internal$$selfFullfillment());
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} else if ($$utils$$objectOrFunction(value)) {
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$$$internal$$handleMaybeThenable(promise, value);
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} else {
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$$$internal$$fulfill(promise, value);
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}
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}
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function $$$internal$$publishRejection(promise) {
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if (promise._onerror) {
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promise._onerror(promise._result);
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}
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$$$internal$$publish(promise);
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}
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function $$$internal$$fulfill(promise, value) {
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if (promise._state !== $$$internal$$PENDING) { return; }
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promise._result = value;
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promise._state = $$$internal$$FULFILLED;
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if (promise._subscribers.length === 0) {
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} else {
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$$asap$$default($$$internal$$publish, promise);
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}
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}
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function $$$internal$$reject(promise, reason) {
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if (promise._state !== $$$internal$$PENDING) { return; }
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promise._state = $$$internal$$REJECTED;
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promise._result = reason;
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$$asap$$default($$$internal$$publishRejection, promise);
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}
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function $$$internal$$subscribe(parent, child, onFulfillment, onRejection) {
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var subscribers = parent._subscribers;
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var length = subscribers.length;
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parent._onerror = null;
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subscribers[length] = child;
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subscribers[length + $$$internal$$FULFILLED] = onFulfillment;
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subscribers[length + $$$internal$$REJECTED] = onRejection;
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if (length === 0 && parent._state) {
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$$asap$$default($$$internal$$publish, parent);
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}
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}
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function $$$internal$$publish(promise) {
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var subscribers = promise._subscribers;
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var settled = promise._state;
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if (subscribers.length === 0) { return; }
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var child, callback, detail = promise._result;
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for (var i = 0; i < subscribers.length; i += 3) {
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child = subscribers[i];
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callback = subscribers[i + settled];
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if (child) {
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$$$internal$$invokeCallback(settled, child, callback, detail);
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} else {
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callback(detail);
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}
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}
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promise._subscribers.length = 0;
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}
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function $$$internal$$ErrorObject() {
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this.error = null;
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}
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var $$$internal$$TRY_CATCH_ERROR = new $$$internal$$ErrorObject();
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function $$$internal$$tryCatch(callback, detail) {
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try {
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return callback(detail);
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} catch(e) {
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$$$internal$$TRY_CATCH_ERROR.error = e;
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return $$$internal$$TRY_CATCH_ERROR;
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}
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}
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function $$$internal$$invokeCallback(settled, promise, callback, detail) {
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var hasCallback = $$utils$$isFunction(callback),
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value, error, succeeded, failed;
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if (hasCallback) {
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value = $$$internal$$tryCatch(callback, detail);
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if (value === $$$internal$$TRY_CATCH_ERROR) {
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failed = true;
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error = value.error;
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value = null;
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} else {
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succeeded = true;
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}
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if (promise === value) {
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$$$internal$$reject(promise, $$$internal$$cannotReturnOwn());
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return;
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}
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} else {
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value = detail;
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succeeded = true;
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}
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if (promise._state !== $$$internal$$PENDING) {
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// noop
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} else if (hasCallback && succeeded) {
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$$$internal$$resolve(promise, value);
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} else if (failed) {
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$$$internal$$reject(promise, error);
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} else if (settled === $$$internal$$FULFILLED) {
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$$$internal$$fulfill(promise, value);
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} else if (settled === $$$internal$$REJECTED) {
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$$$internal$$reject(promise, value);
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}
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}
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function $$$internal$$initializePromise(promise, resolver) {
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try {
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resolver(function resolvePromise(value){
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$$$internal$$resolve(promise, value);
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}, function rejectPromise(reason) {
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$$$internal$$reject(promise, reason);
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});
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} catch(e) {
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$$$internal$$reject(promise, e);
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}
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}
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function $$$enumerator$$makeSettledResult(state, position, value) {
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if (state === $$$internal$$FULFILLED) {
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return {
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state: 'fulfilled',
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value: value
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};
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} else {
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return {
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state: 'rejected',
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reason: value
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};
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}
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}
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function $$$enumerator$$Enumerator(Constructor, input, abortOnReject, label) {
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this._instanceConstructor = Constructor;
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this.promise = new Constructor($$$internal$$noop, label);
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this._abortOnReject = abortOnReject;
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if (this._validateInput(input)) {
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this._input = input;
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this.length = input.length;
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this._remaining = input.length;
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this._init();
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if (this.length === 0) {
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$$$internal$$fulfill(this.promise, this._result);
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} else {
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this.length = this.length || 0;
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this._enumerate();
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if (this._remaining === 0) {
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$$$internal$$fulfill(this.promise, this._result);
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}
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}
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} else {
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$$$internal$$reject(this.promise, this._validationError());
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}
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}
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$$$enumerator$$Enumerator.prototype._validateInput = function(input) {
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return $$utils$$isArray(input);
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};
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$$$enumerator$$Enumerator.prototype._validationError = function() {
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return new Error('Array Methods must be provided an Array');
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};
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$$$enumerator$$Enumerator.prototype._init = function() {
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this._result = new Array(this.length);
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};
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var $$$enumerator$$default = $$$enumerator$$Enumerator;
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$$$enumerator$$Enumerator.prototype._enumerate = function() {
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var length = this.length;
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var promise = this.promise;
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var input = this._input;
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for (var i = 0; promise._state === $$$internal$$PENDING && i < length; i++) {
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this._eachEntry(input[i], i);
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}
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};
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$$$enumerator$$Enumerator.prototype._eachEntry = function(entry, i) {
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var c = this._instanceConstructor;
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if ($$utils$$isMaybeThenable(entry)) {
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if (entry.constructor === c && entry._state !== $$$internal$$PENDING) {
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entry._onerror = null;
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this._settledAt(entry._state, i, entry._result);
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} else {
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this._willSettleAt(c.resolve(entry), i);
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}
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} else {
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this._remaining--;
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this._result[i] = this._makeResult($$$internal$$FULFILLED, i, entry);
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}
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};
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$$$enumerator$$Enumerator.prototype._settledAt = function(state, i, value) {
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var promise = this.promise;
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if (promise._state === $$$internal$$PENDING) {
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this._remaining--;
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if (this._abortOnReject && state === $$$internal$$REJECTED) {
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$$$internal$$reject(promise, value);
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} else {
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this._result[i] = this._makeResult(state, i, value);
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}
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}
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if (this._remaining === 0) {
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$$$internal$$fulfill(promise, this._result);
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}
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};
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$$$enumerator$$Enumerator.prototype._makeResult = function(state, i, value) {
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return value;
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};
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$$$enumerator$$Enumerator.prototype._willSettleAt = function(promise, i) {
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var enumerator = this;
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$$$internal$$subscribe(promise, undefined, function(value) {
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enumerator._settledAt($$$internal$$FULFILLED, i, value);
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}, function(reason) {
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enumerator._settledAt($$$internal$$REJECTED, i, reason);
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});
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};
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var $$promise$all$$default = function all(entries, label) {
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return new $$$enumerator$$default(this, entries, true /* abort on reject */, label).promise;
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};
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var $$promise$race$$default = function race(entries, label) {
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/*jshint validthis:true */
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var Constructor = this;
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var promise = new Constructor($$$internal$$noop, label);
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if (!$$utils$$isArray(entries)) {
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$$$internal$$reject(promise, new TypeError('You must pass an array to race.'));
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return promise;
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}
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var length = entries.length;
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function onFulfillment(value) {
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$$$internal$$resolve(promise, value);
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}
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function onRejection(reason) {
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$$$internal$$reject(promise, reason);
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}
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for (var i = 0; promise._state === $$$internal$$PENDING && i < length; i++) {
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$$$internal$$subscribe(Constructor.resolve(entries[i]), undefined, onFulfillment, onRejection);
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}
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return promise;
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};
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var $$promise$resolve$$default = function resolve(object, label) {
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/*jshint validthis:true */
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var Constructor = this;
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if (object && typeof object === 'object' && object.constructor === Constructor) {
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return object;
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}
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var promise = new Constructor($$$internal$$noop, label);
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$$$internal$$resolve(promise, object);
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return promise;
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};
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var $$promise$reject$$default = function reject(reason, label) {
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/*jshint validthis:true */
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var Constructor = this;
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var promise = new Constructor($$$internal$$noop, label);
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$$$internal$$reject(promise, reason);
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return promise;
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};
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var $$es6$promise$promise$$counter = 0;
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function $$es6$promise$promise$$needsResolver() {
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throw new TypeError('You must pass a resolver function as the first argument to the promise constructor');
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}
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function $$es6$promise$promise$$needsNew() {
|
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throw new TypeError("Failed to construct 'Promise': Please use the 'new' operator, this object constructor cannot be called as a function.");
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}
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var $$es6$promise$promise$$default = $$es6$promise$promise$$Promise;
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/**
|
||
Promise objects represent the eventual result of an asynchronous operation. The
|
||
primary way of interacting with a promise is through its `then` method, which
|
||
registers callbacks to receive either a promise’s eventual value or the reason
|
||
why the promise cannot be fulfilled.
|
||
|
||
Terminology
|
||
-----------
|
||
|
||
- `promise` is an object or function with a `then` method whose behavior conforms to this specification.
|
||
- `thenable` is an object or function that defines a `then` method.
|
||
- `value` is any legal JavaScript value (including undefined, a thenable, or a promise).
|
||
- `exception` is a value that is thrown using the throw statement.
|
||
- `reason` is a value that indicates why a promise was rejected.
|
||
- `settled` the final resting state of a promise, fulfilled or rejected.
|
||
|
||
A promise can be in one of three states: pending, fulfilled, or rejected.
|
||
|
||
Promises that are fulfilled have a fulfillment value and are in the fulfilled
|
||
state. Promises that are rejected have a rejection reason and are in the
|
||
rejected state. A fulfillment value is never a thenable.
|
||
|
||
Promises can also be said to *resolve* a value. If this value is also a
|
||
promise, then the original promise's settled state will match the value's
|
||
settled state. So a promise that *resolves* a promise that rejects will
|
||
itself reject, and a promise that *resolves* a promise that fulfills will
|
||
itself fulfill.
|
||
|
||
|
||
Basic Usage:
|
||
------------
|
||
|
||
```js
|
||
var promise = new Promise(function(resolve, reject) {
|
||
// on success
|
||
resolve(value);
|
||
|
||
// on failure
|
||
reject(reason);
|
||
});
|
||
|
||
promise.then(function(value) {
|
||
// on fulfillment
|
||
}, function(reason) {
|
||
// on rejection
|
||
});
|
||
```
|
||
|
||
Advanced Usage:
|
||
---------------
|
||
|
||
Promises shine when abstracting away asynchronous interactions such as
|
||
`XMLHttpRequest`s.
|
||
|
||
```js
|
||
function getJSON(url) {
|
||
return new Promise(function(resolve, reject){
|
||
var xhr = new XMLHttpRequest();
|
||
|
||
xhr.open('GET', url);
|
||
xhr.onreadystatechange = handler;
|
||
xhr.responseType = 'json';
|
||
xhr.setRequestHeader('Accept', 'application/json');
|
||
xhr.send();
|
||
|
||
function handler() {
|
||
if (this.readyState === this.DONE) {
|
||
if (this.status === 200) {
|
||
resolve(this.response);
|
||
} else {
|
||
reject(new Error('getJSON: `' + url + '` failed with status: [' + this.status + ']'));
|
||
}
|
||
}
|
||
};
|
||
});
|
||
}
|
||
|
||
getJSON('/posts.json').then(function(json) {
|
||
// on fulfillment
|
||
}, function(reason) {
|
||
// on rejection
|
||
});
|
||
```
|
||
|
||
Unlike callbacks, promises are great composable primitives.
|
||
|
||
```js
|
||
Promise.all([
|
||
getJSON('/posts'),
|
||
getJSON('/comments')
|
||
]).then(function(values){
|
||
values[0] // => postsJSON
|
||
values[1] // => commentsJSON
|
||
|
||
return values;
|
||
});
|
||
```
|
||
|
||
@class Promise
|
||
@param {function} resolver
|
||
Useful for tooling.
|
||
@constructor
|
||
*/
|
||
function $$es6$promise$promise$$Promise(resolver) {
|
||
this._id = $$es6$promise$promise$$counter++;
|
||
this._state = undefined;
|
||
this._result = undefined;
|
||
this._subscribers = [];
|
||
|
||
if ($$$internal$$noop !== resolver) {
|
||
if (!$$utils$$isFunction(resolver)) {
|
||
$$es6$promise$promise$$needsResolver();
|
||
}
|
||
|
||
if (!(this instanceof $$es6$promise$promise$$Promise)) {
|
||
$$es6$promise$promise$$needsNew();
|
||
}
|
||
|
||
$$$internal$$initializePromise(this, resolver);
|
||
}
|
||
}
|
||
|
||
$$es6$promise$promise$$Promise.all = $$promise$all$$default;
|
||
$$es6$promise$promise$$Promise.race = $$promise$race$$default;
|
||
$$es6$promise$promise$$Promise.resolve = $$promise$resolve$$default;
|
||
$$es6$promise$promise$$Promise.reject = $$promise$reject$$default;
|
||
|
||
$$es6$promise$promise$$Promise.prototype = {
|
||
constructor: $$es6$promise$promise$$Promise,
|
||
|
||
/**
|
||
The primary way of interacting with a promise is through its `then` method,
|
||
which registers callbacks to receive either a promise's eventual value or the
|
||
reason why the promise cannot be fulfilled.
|
||
|
||
```js
|
||
findUser().then(function(user){
|
||
// user is available
|
||
}, function(reason){
|
||
// user is unavailable, and you are given the reason why
|
||
});
|
||
```
|
||
|
||
Chaining
|
||
--------
|
||
|
||
The return value of `then` is itself a promise. This second, 'downstream'
|
||
promise is resolved with the return value of the first promise's fulfillment
|
||
or rejection handler, or rejected if the handler throws an exception.
|
||
|
||
```js
|
||
findUser().then(function (user) {
|
||
return user.name;
|
||
}, function (reason) {
|
||
return 'default name';
|
||
}).then(function (userName) {
|
||
// If `findUser` fulfilled, `userName` will be the user's name, otherwise it
|
||
// will be `'default name'`
|
||
});
|
||
|
||
findUser().then(function (user) {
|
||
throw new Error('Found user, but still unhappy');
|
||
}, function (reason) {
|
||
throw new Error('`findUser` rejected and we're unhappy');
|
||
}).then(function (value) {
|
||
// never reached
|
||
}, function (reason) {
|
||
// if `findUser` fulfilled, `reason` will be 'Found user, but still unhappy'.
|
||
// If `findUser` rejected, `reason` will be '`findUser` rejected and we're unhappy'.
|
||
});
|
||
```
|
||
If the downstream promise does not specify a rejection handler, rejection reasons will be propagated further downstream.
|
||
|
||
```js
|
||
findUser().then(function (user) {
|
||
throw new PedagogicalException('Upstream error');
|
||
}).then(function (value) {
|
||
// never reached
|
||
}).then(function (value) {
|
||
// never reached
|
||
}, function (reason) {
|
||
// The `PedgagocialException` is propagated all the way down to here
|
||
});
|
||
```
|
||
|
||
Assimilation
|
||
------------
|
||
|
||
Sometimes the value you want to propagate to a downstream promise can only be
|
||
retrieved asynchronously. This can be achieved by returning a promise in the
|
||
fulfillment or rejection handler. The downstream promise will then be pending
|
||
until the returned promise is settled. This is called *assimilation*.
|
||
|
||
```js
|
||
findUser().then(function (user) {
|
||
return findCommentsByAuthor(user);
|
||
}).then(function (comments) {
|
||
// The user's comments are now available
|
||
});
|
||
```
|
||
|
||
If the assimliated promise rejects, then the downstream promise will also reject.
|
||
|
||
```js
|
||
findUser().then(function (user) {
|
||
return findCommentsByAuthor(user);
|
||
}).then(function (comments) {
|
||
// If `findCommentsByAuthor` fulfills, we'll have the value here
|
||
}, function (reason) {
|
||
// If `findCommentsByAuthor` rejects, we'll have the reason here
|
||
});
|
||
```
|
||
|
||
Simple Example
|
||
--------------
|
||
|
||
Synchronous Example
|
||
|
||
```javascript
|
||
var result;
|
||
|
||
try {
|
||
result = findResult();
|
||
// success
|
||
} catch(reason) {
|
||
// failure
|
||
}
|
||
```
|
||
|
||
Errback Example
|
||
|
||
```js
|
||
findResult(function(result, err){
|
||
if (err) {
|
||
// failure
|
||
} else {
|
||
// success
|
||
}
|
||
});
|
||
```
|
||
|
||
Promise Example;
|
||
|
||
```javascript
|
||
findResult().then(function(result){
|
||
// success
|
||
}, function(reason){
|
||
// failure
|
||
});
|
||
```
|
||
|
||
Advanced Example
|
||
--------------
|
||
|
||
Synchronous Example
|
||
|
||
```javascript
|
||
var author, books;
|
||
|
||
try {
|
||
author = findAuthor();
|
||
books = findBooksByAuthor(author);
|
||
// success
|
||
} catch(reason) {
|
||
// failure
|
||
}
|
||
```
|
||
|
||
Errback Example
|
||
|
||
```js
|
||
|
||
function foundBooks(books) {
|
||
|
||
}
|
||
|
||
function failure(reason) {
|
||
|
||
}
|
||
|
||
findAuthor(function(author, err){
|
||
if (err) {
|
||
failure(err);
|
||
// failure
|
||
} else {
|
||
try {
|
||
findBoooksByAuthor(author, function(books, err) {
|
||
if (err) {
|
||
failure(err);
|
||
} else {
|
||
try {
|
||
foundBooks(books);
|
||
} catch(reason) {
|
||
failure(reason);
|
||
}
|
||
}
|
||
});
|
||
} catch(error) {
|
||
failure(err);
|
||
}
|
||
// success
|
||
}
|
||
});
|
||
```
|
||
|
||
Promise Example;
|
||
|
||
```javascript
|
||
findAuthor().
|
||
then(findBooksByAuthor).
|
||
then(function(books){
|
||
// found books
|
||
}).catch(function(reason){
|
||
// something went wrong
|
||
});
|
||
```
|
||
|
||
@method then
|
||
@param {Function} onFulfilled
|
||
@param {Function} onRejected
|
||
Useful for tooling.
|
||
@return {Promise}
|
||
*/
|
||
then: function(onFulfillment, onRejection) {
|
||
var parent = this;
|
||
var state = parent._state;
|
||
|
||
if (state === $$$internal$$FULFILLED && !onFulfillment || state === $$$internal$$REJECTED && !onRejection) {
|
||
return this;
|
||
}
|
||
|
||
var child = new this.constructor($$$internal$$noop);
|
||
var result = parent._result;
|
||
|
||
if (state) {
|
||
var callback = arguments[state - 1];
|
||
$$asap$$default(function(){
|
||
$$$internal$$invokeCallback(state, child, callback, result);
|
||
});
|
||
} else {
|
||
$$$internal$$subscribe(parent, child, onFulfillment, onRejection);
|
||
}
|
||
|
||
return child;
|
||
},
|
||
|
||
/**
|
||
`catch` is simply sugar for `then(undefined, onRejection)` which makes it the same
|
||
as the catch block of a try/catch statement.
|
||
|
||
```js
|
||
function findAuthor(){
|
||
throw new Error('couldn't find that author');
|
||
}
|
||
|
||
// synchronous
|
||
try {
|
||
findAuthor();
|
||
} catch(reason) {
|
||
// something went wrong
|
||
}
|
||
|
||
// async with promises
|
||
findAuthor().catch(function(reason){
|
||
// something went wrong
|
||
});
|
||
```
|
||
|
||
@method catch
|
||
@param {Function} onRejection
|
||
Useful for tooling.
|
||
@return {Promise}
|
||
*/
|
||
'catch': function(onRejection) {
|
||
return this.then(null, onRejection);
|
||
}
|
||
};
|
||
|
||
var $$es6$promise$polyfill$$default = function polyfill() {
|
||
var local;
|
||
|
||
if (typeof global !== 'undefined') {
|
||
local = global;
|
||
} else if (typeof window !== 'undefined' && window.document) {
|
||
local = window;
|
||
} else {
|
||
local = self;
|
||
}
|
||
|
||
var es6PromiseSupport =
|
||
"Promise" in local &&
|
||
// Some of these methods are missing from
|
||
// Firefox/Chrome experimental implementations
|
||
"resolve" in local.Promise &&
|
||
"reject" in local.Promise &&
|
||
"all" in local.Promise &&
|
||
"race" in local.Promise &&
|
||
// Older version of the spec had a resolver object
|
||
// as the arg rather than a function
|
||
(function() {
|
||
var resolve;
|
||
new local.Promise(function(r) { resolve = r; });
|
||
return $$utils$$isFunction(resolve);
|
||
}());
|
||
|
||
if (!es6PromiseSupport) {
|
||
local.Promise = $$es6$promise$promise$$default;
|
||
}
|
||
};
|
||
|
||
var es6$promise$umd$$ES6Promise = {
|
||
'Promise': $$es6$promise$promise$$default,
|
||
'polyfill': $$es6$promise$polyfill$$default
|
||
};
|
||
|
||
/* global define:true module:true window: true */
|
||
if (typeof define === 'function' && define['amd']) {
|
||
define(function() { return es6$promise$umd$$ES6Promise; });
|
||
} else if (typeof module !== 'undefined' && module['exports']) {
|
||
module['exports'] = es6$promise$umd$$ES6Promise;
|
||
} else if (typeof this !== 'undefined') {
|
||
this['ES6Promise'] = es6$promise$umd$$ES6Promise;
|
||
}
|
||
}).call(this); |