From fd51dff8b80ac7a202265837218b1718d27f1b12 Mon Sep 17 00:00:00 2001
From: Jorge Canizales <jcanizales@google.com>
Date: Sat, 8 Aug 2015 16:12:52 -0700
Subject: [PATCH] Clarify invalid-argument message for already-started writers

---
 src/objective-c/RxLibrary/GRXForwardingWriter.m | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/objective-c/RxLibrary/GRXForwardingWriter.m b/src/objective-c/RxLibrary/GRXForwardingWriter.m
index cf8be8c557e..a72be9ace2f 100644
--- a/src/objective-c/RxLibrary/GRXForwardingWriter.m
+++ b/src/objective-c/RxLibrary/GRXForwardingWriter.m
@@ -51,7 +51,8 @@
     return nil;
   }
   if (writer.state != GRXWriterStateNotStarted) {
-    [NSException raise:NSInvalidArgumentException format:@"writer can't be started."];
+    [NSException raise:NSInvalidArgumentException
+                format:@"The writer argument must not have already started."];
   }
   if ((self = [super init])) {
     _writer = writer;