From efa47d298fe218b6867197cb6fa9db42a18ba66b Mon Sep 17 00:00:00 2001
From: Nathan Hourt <themodprobe@protonmail.com>
Date: Sun, 14 Apr 2019 15:41:42 -0500
Subject: [PATCH] Ref #1506: Add object_downcast_t

Allows the more concise expression `object_downcast_t<xyz>` instead of
the old `typename object_downcast<xyz>::type`
---
 libraries/db/include/graphene/db/object_database.hpp | 8 ++++----
 libraries/db/include/graphene/db/object_id.hpp       | 2 ++
 libraries/wallet/wallet.cpp                          | 4 ++--
 programs/js_operation_serializer/main.cpp            | 2 +-
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/libraries/db/include/graphene/db/object_database.hpp b/libraries/db/include/graphene/db/object_database.hpp
index 73807eebb8..c7825572fb 100644
--- a/libraries/db/include/graphene/db/object_database.hpp
+++ b/libraries/db/include/graphene/db/object_database.hpp
@@ -122,13 +122,13 @@ namespace graphene { namespace db {
          }
 
          template<uint8_t SpaceID, uint8_t TypeID>
-         auto find( object_id<SpaceID,TypeID> id )const -> const typename object_downcast<decltype(id)>::type* {
-             return find<typename object_downcast<decltype(id)>::type>(id);
+         auto find( object_id<SpaceID,TypeID> id )const -> const object_downcast_t<decltype(id)>* {
+             return find<object_downcast_t<decltype(id)>>(id);
          }
 
          template<uint8_t SpaceID, uint8_t TypeID>
-         auto get( object_id<SpaceID,TypeID> id )const -> const typename object_downcast<decltype(id)>::type& {
-             return get<typename object_downcast<decltype(id)>::type>(id);
+         auto get( object_id<SpaceID,TypeID> id )const -> const object_downcast_t<decltype(id)>& {
+             return get<object_downcast_t<decltype(id)>>(id);
          }
 
          template<typename IndexType>
diff --git a/libraries/db/include/graphene/db/object_id.hpp b/libraries/db/include/graphene/db/object_id.hpp
index 68de0bd2ac..9bdfe550ea 100644
--- a/libraries/db/include/graphene/db/object_id.hpp
+++ b/libraries/db/include/graphene/db/object_id.hpp
@@ -100,6 +100,8 @@ namespace graphene { namespace db {
    template<> \
    struct object_downcast<graphene::db::object_id<OBJECT::space_id, OBJECT::type_id>> { using type = OBJECT; }; \
    } }
+   template<typename ObjectID>
+   using object_downcast_t = typename object_downcast<ObjectID>::type;
 
    template<uint8_t SpaceID, uint8_t TypeID>
    struct object_id
diff --git a/libraries/wallet/wallet.cpp b/libraries/wallet/wallet.cpp
index e21f43de48..4febf34b2b 100644
--- a/libraries/wallet/wallet.cpp
+++ b/libraries/wallet/wallet.cpp
@@ -533,10 +533,10 @@ class wallet_api_impl
    }
 
    template<typename ID>
-   typename graphene::db::object_downcast<ID>::type get_object(ID id)const
+   typename graphene::db::object_downcast_t<ID>get_object(ID id)const
    {
       auto ob = _remote_db->get_objects({id}).front();
-      return ob.template as<typename graphene::db::object_downcast<ID>::type>( GRAPHENE_MAX_NESTED_OBJECTS );
+      return ob.template as<graphene::db::object_downcast_t<ID>>( GRAPHENE_MAX_NESTED_OBJECTS );
    }
 
    void set_operation_fees( signed_transaction& tx, const fee_schedule& s  )
diff --git a/programs/js_operation_serializer/main.cpp b/programs/js_operation_serializer/main.cpp
index 833e82f8ad..4466ce2efa 100644
--- a/programs/js_operation_serializer/main.cpp
+++ b/programs/js_operation_serializer/main.cpp
@@ -130,7 +130,7 @@ struct js_name<graphene::db::object_id<S,T> >
    static std::string name(){
       using namespace graphene::db;
       return "protocol_id_type \"" +
-             remove_namespace(fc::get_typename<typename object_downcast<object_id<S,T>>::type>::name()) +
+             remove_namespace(fc::get_typename<object_downcast_t<object_id<S,T>>>::name()) +
              "\"";
    };
 };