perf(count): remove tryCatch/errorObject for custom tryCatching, 1.84…

…M -> 1.97M ops/sec

src/operator/count.ts

@@ -3,9 +3,6 @@ import {Operator} from '../Operator';
 import {Observer} from '../Observer';
 import {Subscriber} from '../Subscriber';
 
-import {tryCatch} from '../util/tryCatch';
-import {errorObject} from '../util/errorObject';
-
 /**
  * Returns an observable of a single number that represents the number of items that either:
  * Match a provided predicate function, _or_ if a predicate is not provided, the number
@@ -43,22 +40,30 @@ class CountSubscriber<T> extends Subscriber<T> {
  super(destination);
  }
 
- protected _next(value: T): void {
- const predicate = this.predicate;
- let passed: any = true;
- if (predicate) {
- passed = tryCatch(predicate)(value, this.index++, this.source);
- if (passed === errorObject) {
- this.destination.error(passed.e);
- return;
- }
+ next(value: T): void {
+ if (this.predicate) {
+ this._tryPredicate(value);
+ } else {
+ this.count++;
+ }
+ }
+
+ private _tryPredicate(value: T) {
+ let result: any;
+
+ try {
+ result = this.predicate(value, this.index++, this.source);
+ } catch (err) {
+ this.destination.error(err);
+ return;
  }
- if (passed) {
- this.count += 1;
+
+ if (result) {
+ this.count++;
  }
  }
 
- protected _complete(): void {
+ complete(): void {
  this.destination.next(this.count);
  this.destination.complete();
  }