From 5f2897be0b13f26019b91acb5ee0f5614b26ff79 Mon Sep 17 00:00:00 2001
From: Sonu Kapoor <sonukapoor@gmail.com>
Date: Wed, 11 Dec 2019 13:28:19 -0500
Subject: [PATCH] docs(forms): Update catchError to return an `observable`
 (#34357)

Closes #34323

PR Close #34357
---
 .../form-validation/src/app/shared/alter-ego.directive.ts     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts b/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
index f8230e3195..bf08aa6bd3 100644
--- a/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
+++ b/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
@@ -7,7 +7,7 @@ import {
 } from '@angular/forms';
 import { catchError, map } from 'rxjs/operators';
 import { HeroesService } from './heroes.service';
-import { Observable } from 'rxjs';
+import { Observable, of } from 'rxjs';
 
 // #docregion async-validator
 @Injectable({ providedIn: 'root' })
@@ -19,7 +19,7 @@ export class UniqueAlterEgoValidator implements AsyncValidator {
   ): Promise<ValidationErrors | null> | Observable<ValidationErrors | null> {
     return this.heroesService.isAlterEgoTaken(ctrl.value).pipe(
       map(isTaken => (isTaken ? { uniqueAlterEgo: true } : null)),
-      catchError(() => null)
+      catchError(() => of(null))
     );
   }
 }