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polymer-analyzer

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"use strict"; /** * @license * Copyright (c) 2016 The Polymer Project Authors. All rights reserved. * This code may only be used under the BSD style license found at * http://polymer.github.io/LICENSE.txt * The complete set of authors may be found at * http://polymer.github.io/AUTHORS.txt * The complete set of contributors may be found at * http://polymer.github.io/CONTRIBUTORS.txt * Code distributed by Google as part of the polymer project is also * subject to an additional IP rights grant found at * http://polymer.github.io/PATENTS.txt */ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) { return new (P || (P = Promise))(function (resolve, reject) { function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } } function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } } function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); } step((generator = generator.apply(thisArg, _arguments || [])).next()); }); }; Object.defineProperty(exports, "__esModule", { value: true }); /** * A map from keys to promises of values. Used for caching asynchronous work. */ class AsyncWorkCache { constructor(from) { if (from) { this._keyToResultMap = new Map(from._keyToResultMap); } else { this._keyToResultMap = new Map(); } } /** * If work has already begun to compute the given key, return a promise for * the result of that work. * * If not, compute it with the given function. * * This method ensures that we will only try to compute the value for `key` * once, no matter how often or with what timing getOrCompute is called, even * recursively. */ getOrCompute(key, compute) { return __awaiter(this, void 0, void 0, function* () { const cachedResult = this._keyToResultMap.get(key); if (cachedResult) { return cachedResult; } const promise = (() => __awaiter(this, void 0, void 0, function* () { // Make sure we wait and return a Promise before doing any work, so that // the Promise is cached before control flow enters compute(). yield Promise.resolve(); return compute(); }))(); this._keyToResultMap.set(key, promise); return promise; }); } delete(key) { this._keyToResultMap.delete(key); } clear() { this._keyToResultMap.clear(); } set(key, value) { this._keyToResultMap.set(key, Promise.resolve(value)); } has(key) { return this._keyToResultMap.has(key); } } exports.AsyncWorkCache = AsyncWorkCache; //# sourceMappingURL=async-work-cache.js.map