wed
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Wed is a schema-aware editor for XML documents.
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JavaScript
define(function(require,exports,module){
;
var __extends = (this && this.__extends) || (function () {
var extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
var Observable_1 = require("../Observable");
var isArray_1 = require("../util/isArray");
var empty_1 = require("./empty");
var subscribeToResult_1 = require("../util/subscribeToResult");
var OuterSubscriber_1 = require("../OuterSubscriber");
var map_1 = require("../operators/map");
/* tslint:enable:max-line-length */
/**
* Joins last values emitted by passed Observables.
*
* <span class="informal">Wait for Observables to complete and then combine last values they emitted.</span>
*
* <img src="./img/forkJoin.png" width="100%">
*
* `forkJoin` is an operator that takes any number of Observables which can be passed either as an array
* or directly as arguments. If no input Observables are provided, resulting stream will complete
* immediately.
*
* `forkJoin` will wait for all passed Observables to complete and then it will emit an array with last
* values from corresponding Observables. So if you pass `n` Observables to the operator, resulting
* array will have `n` values, where first value is the last thing emitted by the first Observable,
* second value is the last thing emitted by the second Observable and so on. That means `forkJoin` will
* not emit more than once and it will complete after that. If you need to emit combined values not only
* at the end of lifecycle of passed Observables, but also throughout it, try out {@link combineLatest}
* or {@link zip} instead.
*
* In order for resulting array to have the same length as the number of input Observables, whenever any of
* that Observables completes without emitting any value, `forkJoin` will complete at that moment as well
* and it will not emit anything either, even if it already has some last values from other Observables.
* Conversely, if there is an Observable that never completes, `forkJoin` will never complete as well,
* unless at any point some other Observable completes without emitting value, which brings us back to
* the previous case. Overall, in order for `forkJoin` to emit a value, all Observables passed as arguments
* have to emit something at least once and complete.
*
* If any input Observable errors at some point, `forkJoin` will error as well and all other Observables
* will be immediately unsubscribed.
*
* Optionally `forkJoin` accepts project function, that will be called with values which normally
* would land in emitted array. Whatever is returned by project function, will appear in output
* Observable instead. This means that default project can be thought of as a function that takes
* all its arguments and puts them into an array. Note that project function will be called only
* when output Observable is supposed to emit a result.
*
* @example <caption>Use forkJoin with operator emitting immediately</caption>
* import { forkJoin, of } from 'rxjs';
*
* const observable = forkJoin(
* of(1, 2, 3, 4),
* of(5, 6, 7, 8)
* );
* observable.subscribe(
* value => console.log(value),
* err => {},
* () => console.log('This is how it ends!')
* );
*
* // Logs:
* // [4, 8]
* // "This is how it ends!"
*
*
* @example <caption>Use forkJoin with operator emitting after some time</caption>
* import { forkJoin, interval } from 'rxjs';
* import { take } from 'rxjs/operators';
*
* const observable = forkJoin(
* interval(1000).pipe(take(3)), // emit 0, 1, 2 every second and complete
* interval(500).pipe(take(4)) // emit 0, 1, 2, 3 every half a second and complete
* );
* observable.subscribe(
* value => console.log(value),
* err => {},
* () => console.log('This is how it ends!')
* );
*
* // Logs:
* // [2, 3] after 3 seconds
* // "This is how it ends!" immediately after
*
*
* @example <caption>Use forkJoin with project function</caption>
* import { jorkJoin, interval } from 'rxjs';
* import { take } from 'rxjs/operators';
*
* const observable = forkJoin(
* interval(1000).pipe(take(3)), // emit 0, 1, 2 every second and complete
* interval(500).pipe(take(4)), // emit 0, 1, 2, 3 every half a second and complete
* (n, m) => n + m
* );
* observable.subscribe(
* value => console.log(value),
* err => {},
* () => console.log('This is how it ends!')
* );
*
* // Logs:
* // 5 after 3 seconds
* // "This is how it ends!" immediately after
*
* @see {@link combineLatest}
* @see {@link zip}
*
* @param {...ObservableInput} sources Any number of Observables provided either as an array or as an arguments
* passed directly to the operator.
* @param {function} [project] Function that takes values emitted by input Observables and returns value
* that will appear in resulting Observable instead of default array.
* @return {Observable} Observable emitting either an array of last values emitted by passed Observables
* or value from project function.
*/
function forkJoin() {
var sources = [];
for (var _i = 0; _i < arguments.length; _i++) {
sources[_i] = arguments[_i];
}
var resultSelector;
if (typeof sources[sources.length - 1] === 'function') {
// DEPRECATED PATH
resultSelector = sources.pop();
}
// if the first and only other argument is an array
// assume it's been called with `forkJoin([obs1, obs2, obs3])`
if (sources.length === 1 && isArray_1.isArray(sources[0])) {
sources = sources[0];
}
if (sources.length === 0) {
return empty_1.EMPTY;
}
if (resultSelector) {
// DEPRECATED PATH
return forkJoin(sources).pipe(map_1.map(function (args) { return resultSelector.apply(void 0, args); }));
}
return new Observable_1.Observable(function (subscriber) {
return new ForkJoinSubscriber(subscriber, sources);
});
}
exports.forkJoin = forkJoin;
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var ForkJoinSubscriber = /** @class */ (function (_super) {
__extends(ForkJoinSubscriber, _super);
function ForkJoinSubscriber(destination, sources) {
var _this = _super.call(this, destination) || this;
_this.sources = sources;
_this.completed = 0;
_this.haveValues = 0;
var len = sources.length;
_this.values = new Array(len);
for (var i = 0; i < len; i++) {
var source = sources[i];
var innerSubscription = subscribeToResult_1.subscribeToResult(_this, source, null, i);
if (innerSubscription) {
_this.add(innerSubscription);
}
}
return _this;
}
ForkJoinSubscriber.prototype.notifyNext = function (outerValue, innerValue, outerIndex, innerIndex, innerSub) {
this.values[outerIndex] = innerValue;
if (!innerSub._hasValue) {
innerSub._hasValue = true;
this.haveValues++;
}
};
ForkJoinSubscriber.prototype.notifyComplete = function (innerSub) {
var _a = this, destination = _a.destination, haveValues = _a.haveValues, values = _a.values;
var len = values.length;
if (!innerSub._hasValue) {
destination.complete();
return;
}
this.completed++;
if (this.completed !== len) {
return;
}
if (haveValues === len) {
destination.next(values);
}
destination.complete();
};
return ForkJoinSubscriber;
}(OuterSubscriber_1.OuterSubscriber));
//# sourceMappingURL=forkJoin.js.map
return module.exports;
});