Add serialisation for akrzemi1::optional

This puts cereal from 1.2.2 to the latest develop branch, which includes support for serialising std::optional.
Added support to serialise akrzemi1::optional (copied the function to serialise std::optional).
This allows seemless loading and saving across the two different optionals.

Author: patrikhuber

3rdparty/cereal

@@ -114,6 +114,7 @@ set(HEADERS
   ${CMAKE_CURRENT_SOURCE_DIR}/include/eos/video/keyframe_merging.hpp
   ${CMAKE_CURRENT_SOURCE_DIR}/include/eos/cpp17/optional.hpp
   ${CMAKE_CURRENT_SOURCE_DIR}/include/eos/cpp17/detail/akrzemi1_optional.hpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/include/eos/cpp17/detail/akrzemi1_optional_serialization.hpp
 )
 
 add_library(eos INTERFACE)

CMakeLists.txt

@@ -0,0 +1,64 @@
+/*
+ * eos - A 3D Morphable Model fitting library written in modern C++11/14.
+ *
+ * File: include/eos/cpp17/detail/akrzemi1_optional_serialization.hpp
+ *
+ * Copyright 2018 Patrik Huber
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#pragma once
+
+#ifndef EOS_AKRZEMI1_OPTIONAL_SERIALIZATION_HPP_
+#define EOS_AKRZEMI1_OPTIONAL_SERIALIZATION_HPP_
+
+#include "eos/cpp17/detail/akrzemi1_optional.hpp"
+
+#include "cereal/cereal.hpp"
+
+namespace cereal {
+
+//! Saving for akrzemi1::optional
+template <class Archive, typename T>
+inline void CEREAL_SAVE_FUNCTION_NAME(Archive& ar, const akrzemi1::optional<T>& optional)
+{
+    if (!optional)
+    {
+        ar(CEREAL_NVP_("nullopt", true));
+    } else
+    {
+        ar(CEREAL_NVP_("nullopt", false), CEREAL_NVP_("data", *optional));
+    }
+}
+
+//! Loading for akrzemi1::optional
+template <class Archive, typename T>
+inline void CEREAL_LOAD_FUNCTION_NAME(Archive& ar, akrzemi1::optional<T>& optional)
+{
+    bool nullopt;
+    ar(CEREAL_NVP_("nullopt", nullopt));
+
+    if (nullopt)
+    {
+        optional = akrzemi1::nullopt;
+    } else
+    {
+        T value;
+        ar(CEREAL_NVP_("data", value));
+        optional = std::move(value);
+    }
+}
+
+} // namespace cereal
+
+#endif /* EOS_AKRZEMI1_OPTIONAL_SERIALIZATION_HPP_ */

include/eos/cpp17/detail/akrzemi1_optional_serialization.hpp

@@ -24,6 +24,7 @@
 
 #ifdef __APPLE__
   #include "eos/cpp17/detail/akrzemi1_optional.hpp"
+  #include "eos/cpp17/detail/akrzemi1_optional_serialization.hpp"
   namespace eos {
       namespace cpp17 = ::akrzemi1;
   }