From d31a04bb005a449944114a4ec23e1e4881737e16 Mon Sep 17 00:00:00 2001
From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Tue, 9 Apr 2019 15:03:19 +0200
Subject: [PATCH] Add overload for default constructors

---
 .../deal.II/algorithms/general_data_storage.h  | 18 ++++++++++++++++++
 tests/algorithms/general_data_storage_01.cc    |  6 ++++++
 2 files changed, 24 insertions(+)

diff --git a/include/deal.II/algorithms/general_data_storage.h b/include/deal.II/algorithms/general_data_storage.h
index 07d9075e60..2517b41149 100644
--- a/include/deal.II/algorithms/general_data_storage.h
+++ b/include/deal.II/algorithms/general_data_storage.h
@@ -266,6 +266,13 @@ public:
                               Arg &&             argument,
                               Args &&... arguments);
 
+  /**
+   * Same as above for default constructors.
+   */
+  template <typename Type>
+  Type &
+  get_or_add_object_with_name(const std::string &name);
+
   /**
    * Return a reference to the object with given name.
    *
@@ -475,6 +482,17 @@ GeneralDataStorage::get_or_add_object_with_name(const std::string &name,
 }
 
 
+template <typename Type>
+Type &
+GeneralDataStorage::get_or_add_object_with_name(const std::string &name)
+{
+  if (!stores_object_with_name(name))
+    add_unique_copy(name, Type());
+
+  return get_object_with_name<Type>(name);
+}
+
+
 #endif // DOXYGEN
 
 
diff --git a/tests/algorithms/general_data_storage_01.cc b/tests/algorithms/general_data_storage_01.cc
index 5721492f80..483149a9b8 100644
--- a/tests/algorithms/general_data_storage_01.cc
+++ b/tests/algorithms/general_data_storage_01.cc
@@ -145,6 +145,8 @@ main()
       const double  val_1 = 1.0;
       const double &val_2 =
         data.get_or_add_object_with_name<double>("value", val_1);
+      const std::string &str =
+        data.get_or_add_object_with_name<std::string>("empty string");
     }
 
     // Pass Arguments by rvalue reference
@@ -152,12 +154,16 @@ main()
       double        val_1 = 1.0;
       const double &val_2 =
         data.get_or_add_object_with_name<double>("value", std::move(val_1));
+      const std::string &str =
+        data.get_or_add_object_with_name<std::string>("empty string");
     }
 
     // Pass Arguments ambiguously
     {
       const double &val_2 =
         data.get_or_add_object_with_name<double>("value", 1.0);
+      const std::string &str =
+        data.get_or_add_object_with_name<std::string>("empty string");
     }
   }
 
-- 
2.39.5