switchMap.js 2.95 KB
/** PURE_IMPORTS_START tslib,_map,_observable_from,_innerSubscribe PURE_IMPORTS_END */
import * as tslib_1 from "tslib";
import { map } from './map';
import { from } from '../observable/from';
import { SimpleOuterSubscriber, SimpleInnerSubscriber, innerSubscribe } from '../innerSubscribe';
export function switchMap(project, resultSelector) {
    if (typeof resultSelector === 'function') {
        return function (source) { return source.pipe(switchMap(function (a, i) { return from(project(a, i)).pipe(map(function (b, ii) { return resultSelector(a, b, i, ii); })); })); };
    }
    return function (source) { return source.lift(new SwitchMapOperator(project)); };
}
var SwitchMapOperator = /*@__PURE__*/ (function () {
    function SwitchMapOperator(project) {
        this.project = project;
    }
    SwitchMapOperator.prototype.call = function (subscriber, source) {
        return source.subscribe(new SwitchMapSubscriber(subscriber, this.project));
    };
    return SwitchMapOperator;
}());
var SwitchMapSubscriber = /*@__PURE__*/ (function (_super) {
    tslib_1.__extends(SwitchMapSubscriber, _super);
    function SwitchMapSubscriber(destination, project) {
        var _this = _super.call(this, destination) || this;
        _this.project = project;
        _this.index = 0;
        return _this;
    }
    SwitchMapSubscriber.prototype._next = function (value) {
        var result;
        var index = this.index++;
        try {
            result = this.project(value, index);
        }
        catch (error) {
            this.destination.error(error);
            return;
        }
        this._innerSub(result);
    };
    SwitchMapSubscriber.prototype._innerSub = function (result) {
        var innerSubscription = this.innerSubscription;
        if (innerSubscription) {
            innerSubscription.unsubscribe();
        }
        var innerSubscriber = new SimpleInnerSubscriber(this);
        var destination = this.destination;
        destination.add(innerSubscriber);
        this.innerSubscription = innerSubscribe(result, innerSubscriber);
        if (this.innerSubscription !== innerSubscriber) {
            destination.add(this.innerSubscription);
        }
    };
    SwitchMapSubscriber.prototype._complete = function () {
        var innerSubscription = this.innerSubscription;
        if (!innerSubscription || innerSubscription.closed) {
            _super.prototype._complete.call(this);
        }
        this.unsubscribe();
    };
    SwitchMapSubscriber.prototype._unsubscribe = function () {
        this.innerSubscription = undefined;
    };
    SwitchMapSubscriber.prototype.notifyComplete = function () {
        this.innerSubscription = undefined;
        if (this.isStopped) {
            _super.prototype._complete.call(this);
        }
    };
    SwitchMapSubscriber.prototype.notifyNext = function (innerValue) {
        this.destination.next(innerValue);
    };
    return SwitchMapSubscriber;
}(SimpleOuterSubscriber));
//# sourceMappingURL=switchMap.js.map