255 lines
7.4 KiB
JavaScript
Executable File
255 lines
7.4 KiB
JavaScript
Executable File
import { ArrayObservable } from '../observable/ArrayObservable';
|
|
import { isArray } from '../util/isArray';
|
|
import { Subscriber } from '../Subscriber';
|
|
import { OuterSubscriber } from '../OuterSubscriber';
|
|
import { subscribeToResult } from '../util/subscribeToResult';
|
|
import { iterator as Symbol_iterator } from '../symbol/iterator';
|
|
/* tslint:enable:max-line-length */
|
|
/**
|
|
* @param observables
|
|
* @return {Observable<R>}
|
|
* @method zip
|
|
* @owner Observable
|
|
*/
|
|
export function zip(...observables) {
|
|
return function zipOperatorFunction(source) {
|
|
return source.lift.call(zipStatic(source, ...observables));
|
|
};
|
|
}
|
|
/* tslint:enable:max-line-length */
|
|
/**
|
|
* Combines multiple Observables to create an Observable whose values are calculated from the values, in order, of each
|
|
* of its input Observables.
|
|
*
|
|
* If the latest parameter is a function, this function is used to compute the created value from the input values.
|
|
* Otherwise, an array of the input values is returned.
|
|
*
|
|
* @example <caption>Combine age and name from different sources</caption>
|
|
*
|
|
* let age$ = Observable.of<number>(27, 25, 29);
|
|
* let name$ = Observable.of<string>('Foo', 'Bar', 'Beer');
|
|
* let isDev$ = Observable.of<boolean>(true, true, false);
|
|
*
|
|
* Observable
|
|
* .zip(age$,
|
|
* name$,
|
|
* isDev$,
|
|
* (age: number, name: string, isDev: boolean) => ({ age, name, isDev }))
|
|
* .subscribe(x => console.log(x));
|
|
*
|
|
* // outputs
|
|
* // { age: 27, name: 'Foo', isDev: true }
|
|
* // { age: 25, name: 'Bar', isDev: true }
|
|
* // { age: 29, name: 'Beer', isDev: false }
|
|
*
|
|
* @param observables
|
|
* @return {Observable<R>}
|
|
* @static true
|
|
* @name zip
|
|
* @owner Observable
|
|
*/
|
|
export function zipStatic(...observables) {
|
|
const project = observables[observables.length - 1];
|
|
if (typeof project === 'function') {
|
|
observables.pop();
|
|
}
|
|
return new ArrayObservable(observables).lift(new ZipOperator(project));
|
|
}
|
|
export class ZipOperator {
|
|
constructor(project) {
|
|
this.project = project;
|
|
}
|
|
call(subscriber, source) {
|
|
return source.subscribe(new ZipSubscriber(subscriber, this.project));
|
|
}
|
|
}
|
|
/**
|
|
* We need this JSDoc comment for affecting ESDoc.
|
|
* @ignore
|
|
* @extends {Ignored}
|
|
*/
|
|
export class ZipSubscriber extends Subscriber {
|
|
constructor(destination, project, values = Object.create(null)) {
|
|
super(destination);
|
|
this.iterators = [];
|
|
this.active = 0;
|
|
this.project = (typeof project === 'function') ? project : null;
|
|
this.values = values;
|
|
}
|
|
_next(value) {
|
|
const iterators = this.iterators;
|
|
if (isArray(value)) {
|
|
iterators.push(new StaticArrayIterator(value));
|
|
}
|
|
else if (typeof value[Symbol_iterator] === 'function') {
|
|
iterators.push(new StaticIterator(value[Symbol_iterator]()));
|
|
}
|
|
else {
|
|
iterators.push(new ZipBufferIterator(this.destination, this, value));
|
|
}
|
|
}
|
|
_complete() {
|
|
const iterators = this.iterators;
|
|
const len = iterators.length;
|
|
if (len === 0) {
|
|
this.destination.complete();
|
|
return;
|
|
}
|
|
this.active = len;
|
|
for (let i = 0; i < len; i++) {
|
|
let iterator = iterators[i];
|
|
if (iterator.stillUnsubscribed) {
|
|
this.add(iterator.subscribe(iterator, i));
|
|
}
|
|
else {
|
|
this.active--; // not an observable
|
|
}
|
|
}
|
|
}
|
|
notifyInactive() {
|
|
this.active--;
|
|
if (this.active === 0) {
|
|
this.destination.complete();
|
|
}
|
|
}
|
|
checkIterators() {
|
|
const iterators = this.iterators;
|
|
const len = iterators.length;
|
|
const destination = this.destination;
|
|
// abort if not all of them have values
|
|
for (let i = 0; i < len; i++) {
|
|
let iterator = iterators[i];
|
|
if (typeof iterator.hasValue === 'function' && !iterator.hasValue()) {
|
|
return;
|
|
}
|
|
}
|
|
let shouldComplete = false;
|
|
const args = [];
|
|
for (let i = 0; i < len; i++) {
|
|
let iterator = iterators[i];
|
|
let result = iterator.next();
|
|
// check to see if it's completed now that you've gotten
|
|
// the next value.
|
|
if (iterator.hasCompleted()) {
|
|
shouldComplete = true;
|
|
}
|
|
if (result.done) {
|
|
destination.complete();
|
|
return;
|
|
}
|
|
args.push(result.value);
|
|
}
|
|
if (this.project) {
|
|
this._tryProject(args);
|
|
}
|
|
else {
|
|
destination.next(args);
|
|
}
|
|
if (shouldComplete) {
|
|
destination.complete();
|
|
}
|
|
}
|
|
_tryProject(args) {
|
|
let result;
|
|
try {
|
|
result = this.project.apply(this, args);
|
|
}
|
|
catch (err) {
|
|
this.destination.error(err);
|
|
return;
|
|
}
|
|
this.destination.next(result);
|
|
}
|
|
}
|
|
class StaticIterator {
|
|
constructor(iterator) {
|
|
this.iterator = iterator;
|
|
this.nextResult = iterator.next();
|
|
}
|
|
hasValue() {
|
|
return true;
|
|
}
|
|
next() {
|
|
const result = this.nextResult;
|
|
this.nextResult = this.iterator.next();
|
|
return result;
|
|
}
|
|
hasCompleted() {
|
|
const nextResult = this.nextResult;
|
|
return nextResult && nextResult.done;
|
|
}
|
|
}
|
|
class StaticArrayIterator {
|
|
constructor(array) {
|
|
this.array = array;
|
|
this.index = 0;
|
|
this.length = 0;
|
|
this.length = array.length;
|
|
}
|
|
[Symbol_iterator]() {
|
|
return this;
|
|
}
|
|
next(value) {
|
|
const i = this.index++;
|
|
const array = this.array;
|
|
return i < this.length ? { value: array[i], done: false } : { value: null, done: true };
|
|
}
|
|
hasValue() {
|
|
return this.array.length > this.index;
|
|
}
|
|
hasCompleted() {
|
|
return this.array.length === this.index;
|
|
}
|
|
}
|
|
/**
|
|
* We need this JSDoc comment for affecting ESDoc.
|
|
* @ignore
|
|
* @extends {Ignored}
|
|
*/
|
|
class ZipBufferIterator extends OuterSubscriber {
|
|
constructor(destination, parent, observable) {
|
|
super(destination);
|
|
this.parent = parent;
|
|
this.observable = observable;
|
|
this.stillUnsubscribed = true;
|
|
this.buffer = [];
|
|
this.isComplete = false;
|
|
}
|
|
[Symbol_iterator]() {
|
|
return this;
|
|
}
|
|
// NOTE: there is actually a name collision here with Subscriber.next and Iterator.next
|
|
// this is legit because `next()` will never be called by a subscription in this case.
|
|
next() {
|
|
const buffer = this.buffer;
|
|
if (buffer.length === 0 && this.isComplete) {
|
|
return { value: null, done: true };
|
|
}
|
|
else {
|
|
return { value: buffer.shift(), done: false };
|
|
}
|
|
}
|
|
hasValue() {
|
|
return this.buffer.length > 0;
|
|
}
|
|
hasCompleted() {
|
|
return this.buffer.length === 0 && this.isComplete;
|
|
}
|
|
notifyComplete() {
|
|
if (this.buffer.length > 0) {
|
|
this.isComplete = true;
|
|
this.parent.notifyInactive();
|
|
}
|
|
else {
|
|
this.destination.complete();
|
|
}
|
|
}
|
|
notifyNext(outerValue, innerValue, outerIndex, innerIndex, innerSub) {
|
|
this.buffer.push(innerValue);
|
|
this.parent.checkIterators();
|
|
}
|
|
subscribe(value, index) {
|
|
return subscribeToResult(this, this.observable, this, index);
|
|
}
|
|
}
|
|
//# sourceMappingURL=zip.js.map
|