From 3e0c6d900f5f48c2e2b2815043616e666796f922 Mon Sep 17 00:00:00 2001
From: OJ Kwon <kwon.ohjoong@gmail.com>
Date: Mon, 20 Jun 2016 12:57:26 -0700
Subject: [PATCH] fix(Subject): allow optional next value in type definition

closes #1728
---
 src/Subject.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Subject.ts b/src/Subject.ts
index a970cc6aa2..257cb3ab2d 100644
--- a/src/Subject.ts
+++ b/src/Subject.ts
@@ -49,7 +49,7 @@ export class Subject<T> extends Observable<T> implements ISubscription {
     return <any>subject;
   }
 
-  next(value: T) {
+  next(value?: T) {
     if (this.isUnsubscribed) {
       throw new ObjectUnsubscribedError();
     }