@reactivex/rxjs

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class="source-code line-number raw-source-code"><code class="prettyprint linenums" data-ice="content">import { Subscriber } from '../Subscriber'; import { EmptyError } from '../util/EmptyError'; /* tslint:disable:max-line-length */ export function first(predicate, resultSelector, defaultValue) { return this.lift(new FirstOperator(predicate, resultSelector, defaultValue, this)); } var FirstOperator = (function () { function FirstOperator(predicate, resultSelector, defaultValue, source) { this.predicate = predicate; this.resultSelector = resultSelector; this.defaultValue = defaultValue; this.source = source; } FirstOperator.prototype.call = function (observer, source) { return source._subscribe(new FirstSubscriber(observer, this.predicate, this.resultSelector, this.defaultValue, this.source)); }; return FirstOperator; }()); /** * We need this JSDoc comment for affecting ESDoc. * @ignore * @extends {Ignored} */ var FirstSubscriber = (function (_super) { __extends(FirstSubscriber, _super); function FirstSubscriber(destination, predicate, resultSelector, defaultValue, source) { _super.call(this, destination); this.predicate = predicate; this.resultSelector = resultSelector; this.defaultValue = defaultValue; this.source = source; this.index = 0; this.hasCompleted = false; this._emitted = false; } FirstSubscriber.prototype._next = function (value) { var index = this.index++; if (this.predicate) { this._tryPredicate(value, index); } else { this._emit(value, index); } }; FirstSubscriber.prototype._tryPredicate = function (value, index) { var result; try { result = this.predicate(value, index, this.source); } catch (err) { this.destination.error(err); return; } if (result) { this._emit(value, index); } }; FirstSubscriber.prototype._emit = function (value, index) { if (this.resultSelector) { this._tryResultSelector(value, index); return; } this._emitFinal(value); }; FirstSubscriber.prototype._tryResultSelector = function (value, index) { var result; try { result = this.resultSelector(value, index); } catch (err) { this.destination.error(err); return; } this._emitFinal(result); }; FirstSubscriber.prototype._emitFinal = function (value) { var destination = this.destination; if (!this._emitted) { this._emitted = true; destination.next(value); destination.complete(); this.hasCompleted = true; } }; FirstSubscriber.prototype._complete = function () { var destination = this.destination; if (!this.hasCompleted && typeof this.defaultValue !== 'undefined') { destination.next(this.defaultValue); destination.complete(); } else if (!this.hasCompleted) { destination.error(new EmptyError); } }; return FirstSubscriber; }(Subscriber)); //# sourceMappingURL=first.js.map</code></pre> </div> <footer class="footer"> Generated by <a href="https://esdoc.org">ESDoc<span data-ice="esdocVersion">(0.4.8)</span></a> </footer> <script src="script/search_index.js"></script> <script src="script/search.js"></script> <script src="script/pretty-print.js"></script> <script 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