@reactivex/rxjs
Version:
Reactive Extensions for modern JavaScript
246 lines • 9.88 kB
JavaScript
var __extends = (this && this.__extends) || function (d, b) {
for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
define(["require", "exports", '../Subscriber', '../Subscription', '../Observable', '../Subject', '../util/Map', '../util/FastMap'], function (require, exports, Subscriber_1, Subscription_1, Observable_1, Subject_1, Map_1, FastMap_1) {
"use strict";
/**
* Groups the items emitted by an Observable according to a specified criterion,
* and emits these grouped items as `GroupedObservables`, one
* {@link GroupedObservable} per group.
*
* <img src="./img/groupBy.png" width="100%">
*
* @param {function(value: T): K} keySelector a function that extracts the key
* for each item.
* @param {function(value: T): R} [elementSelector] a function that extracts the
* return element for each item.
* @param {function(grouped: GroupedObservable<K,R>): Observable<any>} [durationSelector]
* a function that returns an Observable to determine how long each group should
* exist.
* @return {Observable<GroupedObservable<K,R>>} an Observable that emits
* GroupedObservables, each of which corresponds to a unique key value and each
* of which emits those items from the source Observable that share that key
* value.
* @method groupBy
* @owner Observable
*/
function groupBy(keySelector, elementSelector, durationSelector) {
return this.lift(new GroupByOperator(this, keySelector, elementSelector, durationSelector));
}
exports.groupBy = groupBy;
var GroupByOperator = (function () {
function GroupByOperator(source, keySelector, elementSelector, durationSelector) {
this.source = source;
this.keySelector = keySelector;
this.elementSelector = elementSelector;
this.durationSelector = durationSelector;
}
GroupByOperator.prototype.call = function (subscriber, source) {
return source._subscribe(new GroupBySubscriber(subscriber, this.keySelector, this.elementSelector, this.durationSelector));
};
return GroupByOperator;
}());
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var GroupBySubscriber = (function (_super) {
__extends(GroupBySubscriber, _super);
function GroupBySubscriber(destination, keySelector, elementSelector, durationSelector) {
_super.call(this);
this.keySelector = keySelector;
this.elementSelector = elementSelector;
this.durationSelector = durationSelector;
this.groups = null;
this.attemptedToUnsubscribe = false;
this.count = 0;
this.destination = destination;
this.add(destination);
}
GroupBySubscriber.prototype._next = function (value) {
var key;
try {
key = this.keySelector(value);
}
catch (err) {
this.error(err);
return;
}
this._group(value, key);
};
GroupBySubscriber.prototype._group = function (value, key) {
var groups = this.groups;
if (!groups) {
groups = this.groups = typeof key === 'string' ? new FastMap_1.FastMap() : new Map_1.Map();
}
var group = groups.get(key);
if (!group) {
groups.set(key, group = new Subject_1.Subject());
var groupedObservable = new GroupedObservable(key, group, this);
if (this.durationSelector) {
this._selectDuration(key, group);
}
this.destination.next(groupedObservable);
}
if (this.elementSelector) {
this._selectElement(value, group);
}
else {
this.tryGroupNext(value, group);
}
};
GroupBySubscriber.prototype._selectElement = function (value, group) {
var result;
try {
result = this.elementSelector(value);
}
catch (err) {
this.error(err);
return;
}
this.tryGroupNext(result, group);
};
GroupBySubscriber.prototype._selectDuration = function (key, group) {
var duration;
try {
duration = this.durationSelector(new GroupedObservable(key, group));
}
catch (err) {
this.error(err);
return;
}
this.add(duration.subscribe(new GroupDurationSubscriber(key, group, this)));
};
GroupBySubscriber.prototype.tryGroupNext = function (value, group) {
if (!group.isUnsubscribed) {
group.next(value);
}
};
GroupBySubscriber.prototype._error = function (err) {
var groups = this.groups;
if (groups) {
groups.forEach(function (group, key) {
group.error(err);
});
groups.clear();
}
this.destination.error(err);
};
GroupBySubscriber.prototype._complete = function () {
var groups = this.groups;
if (groups) {
groups.forEach(function (group, key) {
group.complete();
});
groups.clear();
}
this.destination.complete();
};
GroupBySubscriber.prototype.removeGroup = function (key) {
this.groups.delete(key);
};
GroupBySubscriber.prototype.unsubscribe = function () {
if (!this.isUnsubscribed && !this.attemptedToUnsubscribe) {
this.attemptedToUnsubscribe = true;
if (this.count === 0) {
_super.prototype.unsubscribe.call(this);
}
}
};
return GroupBySubscriber;
}(Subscriber_1.Subscriber));
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var GroupDurationSubscriber = (function (_super) {
__extends(GroupDurationSubscriber, _super);
function GroupDurationSubscriber(key, group, parent) {
_super.call(this);
this.key = key;
this.group = group;
this.parent = parent;
}
GroupDurationSubscriber.prototype._next = function (value) {
this.tryComplete();
};
GroupDurationSubscriber.prototype._error = function (err) {
this.tryError(err);
};
GroupDurationSubscriber.prototype._complete = function () {
this.tryComplete();
};
GroupDurationSubscriber.prototype.tryError = function (err) {
var group = this.group;
if (!group.isUnsubscribed) {
group.error(err);
}
this.parent.removeGroup(this.key);
};
GroupDurationSubscriber.prototype.tryComplete = function () {
var group = this.group;
if (!group.isUnsubscribed) {
group.complete();
}
this.parent.removeGroup(this.key);
};
return GroupDurationSubscriber;
}(Subscriber_1.Subscriber));
/**
* An Observable representing values belonging to the same group represented by
* a common key. The values emitted by a GroupedObservable come from the source
* Observable. The common key is available as the field `key` on a
* GroupedObservable instance.
*
* @class GroupedObservable<K, T>
*/
var GroupedObservable = (function (_super) {
__extends(GroupedObservable, _super);
function GroupedObservable(key, groupSubject, refCountSubscription) {
_super.call(this);
this.key = key;
this.groupSubject = groupSubject;
this.refCountSubscription = refCountSubscription;
}
GroupedObservable.prototype._subscribe = function (subscriber) {
var subscription = new Subscription_1.Subscription();
var _a = this, refCountSubscription = _a.refCountSubscription, groupSubject = _a.groupSubject;
if (refCountSubscription && !refCountSubscription.isUnsubscribed) {
subscription.add(new InnerRefCountSubscription(refCountSubscription));
}
subscription.add(groupSubject.subscribe(subscriber));
return subscription;
};
return GroupedObservable;
}(Observable_1.Observable));
exports.GroupedObservable = GroupedObservable;
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var InnerRefCountSubscription = (function (_super) {
__extends(InnerRefCountSubscription, _super);
function InnerRefCountSubscription(parent) {
_super.call(this);
this.parent = parent;
parent.count++;
}
InnerRefCountSubscription.prototype.unsubscribe = function () {
var parent = this.parent;
if (!parent.isUnsubscribed && !this.isUnsubscribed) {
_super.prototype.unsubscribe.call(this);
parent.count -= 1;
if (parent.count === 0 && parent.attemptedToUnsubscribe) {
parent.unsubscribe();
}
}
};
return InnerRefCountSubscription;
}(Subscription_1.Subscription));
});
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