From 8d05e4e05eed319c8e61baf3d0c48defe7786e93 Mon Sep 17 00:00:00 2001
From: rbock <rbock@eudoxos.de>
Date: Thu, 28 Jun 2018 19:20:09 +0200
Subject: [PATCH] Add serializer for value_or_null

---
 include/sqlpp11/value_or_null.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/include/sqlpp11/value_or_null.h b/include/sqlpp11/value_or_null.h
index 0643d5ad..788f1899 100644
--- a/include/sqlpp11/value_or_null.h
+++ b/include/sqlpp11/value_or_null.h
@@ -52,6 +52,27 @@ namespace sqlpp
     bool _is_null;
   };
 
+  template <typename Context, typename ValueType>
+  struct serializer_t<Context, value_or_null_t<ValueType>>
+  {
+    using _serialize_check = consistent_t;
+    using Operand = value_or_null_t<ValueType>;
+
+    static Context& _(const Operand& t, Context& context)
+    {
+      if (t._is_null)
+      {
+        context << "NULL";
+      }
+      else
+      {
+        serialize(wrap_operand_t<typename ValueType::_cpp_value_type>{t._value}, context);
+      }
+
+      return context;
+    }
+  };
+
   template <typename T>
   auto value_or_null(T t) -> value_or_null_t<value_type_of<wrap_operand_t<T>>>
   {