51 lines
1.7 KiB
JavaScript
51 lines
1.7 KiB
JavaScript
import { Subscriber } from '../Subscriber';
|
|
export function find(predicate, thisArg) {
|
|
if (typeof predicate !== 'function') {
|
|
throw new TypeError('predicate is not a function');
|
|
}
|
|
return (source) => source.lift(new FindValueOperator(predicate, source, false, thisArg));
|
|
}
|
|
export class FindValueOperator {
|
|
constructor(predicate, source, yieldIndex, thisArg) {
|
|
this.predicate = predicate;
|
|
this.source = source;
|
|
this.yieldIndex = yieldIndex;
|
|
this.thisArg = thisArg;
|
|
}
|
|
call(observer, source) {
|
|
return source.subscribe(new FindValueSubscriber(observer, this.predicate, this.source, this.yieldIndex, this.thisArg));
|
|
}
|
|
}
|
|
export class FindValueSubscriber extends Subscriber {
|
|
constructor(destination, predicate, source, yieldIndex, thisArg) {
|
|
super(destination);
|
|
this.predicate = predicate;
|
|
this.source = source;
|
|
this.yieldIndex = yieldIndex;
|
|
this.thisArg = thisArg;
|
|
this.index = 0;
|
|
}
|
|
notifyComplete(value) {
|
|
const destination = this.destination;
|
|
destination.next(value);
|
|
destination.complete();
|
|
this.unsubscribe();
|
|
}
|
|
_next(value) {
|
|
const { predicate, thisArg } = this;
|
|
const index = this.index++;
|
|
try {
|
|
const result = predicate.call(thisArg || this, value, index, this.source);
|
|
if (result) {
|
|
this.notifyComplete(this.yieldIndex ? index : value);
|
|
}
|
|
}
|
|
catch (err) {
|
|
this.destination.error(err);
|
|
}
|
|
}
|
|
_complete() {
|
|
this.notifyComplete(this.yieldIndex ? -1 : undefined);
|
|
}
|
|
}
|
|
//# sourceMappingURL=find.js.map
|