Added alias

src/emitter.cpp

@@ -512,7 +512,19 @@ namespace YAML
 	{
 		if(!good())
 			return *this;
+        
+        if(m_pState->HasAnchor() || m_pState->HasTag()) {
+            m_pState->SetError(ErrorMsg::INVALID_ALIAS);
+            return *this;
+        }
 
+        PrepareNode(EmitterNodeType::Scalar);
+
+		if(!Utils::WriteAlias(m_stream, alias.content)) {
+			m_pState->SetError(ErrorMsg::INVALID_ALIAS);
+			return *this;
+		}
+        
         m_pState->BeginScalar();
 
 		return *this;

util/sandbox.cpp

@@ -9,13 +9,13 @@ int main()
     out << "foo";
     out << YAML::LocalTag("hi") << "bar";
     out << YAML::Anchor("asdf") << YAML::BeginMap;
-    out << "a" << "b" << "c" << YAML::Newline;
+    out << "a" << "b" << "c";
     out << YAML::Anchor("a") << YAML::BeginMap;
-    out << "a" << "b";
+    out << YAML::Anchor("d") << "a" << "b";
     out << YAML::EndMap;
     out << YAML::EndMap;
     out << YAML::LocalTag("hi") << YAML::BeginSeq;
-    out << "a" << "b";
+    out << "a" << "b" << YAML::Alias("monkey");
     out << YAML::EndSeq;
     out << YAML::EndSeq;