prex/out/lib/pulsar.js

"use strict";
/*! *****************************************************************************
Copyright (c) Microsoft Corporation.
Licensed under the Apache License, Version 2.0.

See LICENSE file in the project root for details.
***************************************************************************** */
Object.defineProperty(exports, "__esModule", { value: true });
const list_1 = require("./list");
const cancellation_1 = require("./cancellation");
const adapter_1 = require("./adapter");
/**
 * Asynchronously notifies one or more waiting Promises that an event has occurred.
 */
class Pulsar {
    constructor() {
        this._waiters = new list_1.LinkedList();
    }
    /**
     * Notifies the next waiter.
     */
    pulse() {
        const waiter = this._waiters.shift();
        if (waiter)
            waiter();
    }
    /**
     * Notifies all waiters.
     */
    pulseAll() {
        for (const waiter of this._waiters.drain()) {
            if (waiter)
                waiter();
        }
    }
    /**
     * Asynchronously waits for the the next pulse.
     *
     * @param token A CancellationToken used to cancel the request.
     */
    wait(token) {
        return new Promise((resolve, reject) => {
            const _token = adapter_1.getToken(token);
            _token.throwIfCancellationRequested();
            const node = this._waiters.push(() => {
                registration.unregister();
                resolve();
            });
            const registration = _token.register(() => {
                node.list.deleteNode(node);
                reject(new cancellation_1.CancelError());
            });
        });
    }
}
exports.Pulsar = Pulsar;