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1"use strict";
2/*
3 * Copyright The OpenTelemetry Authors
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17Object.defineProperty(exports, "__esModule", { value: true });
18exports.BindOnceFuture = void 0;
19const promise_1 = require("./promise");
20/**
21 * Bind the callback and only invoke the callback once regardless how many times `BindOnceFuture.call` is invoked.
22 */
23class BindOnceFuture {
24 constructor(_callback, _that) {
25 this._callback = _callback;
26 this._that = _that;
27 this._isCalled = false;
28 this._deferred = new promise_1.Deferred();
29 }
30 get isCalled() {
31 return this._isCalled;
32 }
33 get promise() {
34 return this._deferred.promise;
35 }
36 call(...args) {
37 if (!this._isCalled) {
38 this._isCalled = true;
39 try {
40 Promise.resolve(this._callback.call(this._that, ...args))
41 .then(val => this._deferred.resolve(val), err => this._deferred.reject(err));
42 }
43 catch (err) {
44 this._deferred.reject(err);
45 }
46 }
47 return this._deferred.promise;
48 }
49}
50exports.BindOnceFuture = BindOnceFuture;
51//# sourceMappingURL=callback.js.map
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