48 lines
1.2 KiB
JavaScript
48 lines
1.2 KiB
JavaScript
|
import { Subscriber } from '../Subscriber';
|
||
|
|
export function count(predicate) {
|
||
|
|
return (source) => source.lift(new CountOperator(predicate, source));
|
||
|
|
}
|
||
|
|
class CountOperator {
|
||
|
|
constructor(predicate, source) {
|
||
|
|
this.predicate = predicate;
|
||
|
|
this.source = source;
|
||
|
|
}
|
||
|
|
call(subscriber, source) {
|
||
|
|
return source.subscribe(new CountSubscriber(subscriber, this.predicate, this.source));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
class CountSubscriber extends Subscriber {
|
||
|
|
constructor(destination, predicate, source) {
|
||
|
|
super(destination);
|
||
|
|
this.predicate = predicate;
|
||
|
|
this.source = source;
|
||
|
|
this.count = 0;
|
||
|
|
this.index = 0;
|
||
|
|
}
|
||
|
|
_next(value) {
|
||
|
|
if (this.predicate) {
|
||
|
|
this._tryPredicate(value);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
this.count++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
_tryPredicate(value) {
|
||
|
|
let result;
|
||
|
|
try {
|
||
|
|
result = this.predicate(value, this.index++, this.source);
|
||
|
|
}
|
||
|
|
catch (err) {
|
||
|
|
this.destination.error(err);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (result) {
|
||
|
|
this.count++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
_complete() {
|
||
|
|
this.destination.next(this.count);
|
||
|
|
this.destination.complete();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
//# sourceMappingURL=count.js.map
|