src, test: Remove header guards

Because of `sqlite_modern_cpp.h` as a dependency, libdjinterop
can already only be compiled with a compiler that supports
`#pragma once`. Therefore, we can remove header guards from all
headers in `./src/` and `./test/`. Header guards are still
present in `./include`. This way, libdjinterop can still be
used in a project compiled without `#pragma once` support.

22 files changed, 247 insertions, 69 deletions

diff --git a/src/djinterop/enginelibrary.cpp b/src/djinterop/enginelibrary.cpp
index 94c7446..43c02c6 100644
--- a/src/djinterop/enginelibrary.cpp
+++ b/src/djinterop/enginelibrary.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <sys/stat.h>
 #include <cmath>
 #include <string>
diff --git a/src/djinterop/enginelibrary/el_crate_impl.cpp b/src/djinterop/enginelibrary/el_crate_impl.cpp
index f755790..03e5169 100644
--- a/src/djinterop/enginelibrary/el_crate_impl.cpp
+++ b/src/djinterop/enginelibrary/el_crate_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <sqlite_modern_cpp.h>
 
 #include <djinterop/djinterop.hpp>
diff --git a/src/djinterop/enginelibrary/el_crate_impl.hpp b/src/djinterop/enginelibrary/el_crate_impl.hpp
index 7381f0a..d9083bf 100644
--- a/src/djinterop/enginelibrary/el_crate_impl.hpp
+++ b/src/djinterop/enginelibrary/el_crate_impl.hpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #pragma once
 
 #include <djinterop/impl/crate_impl.hpp>
diff --git a/src/djinterop/enginelibrary/el_database_impl.cpp b/src/djinterop/enginelibrary/el_database_impl.cpp
index 04e57de..e8283e0 100644
--- a/src/djinterop/enginelibrary/el_database_impl.cpp
+++ b/src/djinterop/enginelibrary/el_database_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <djinterop/djinterop.hpp>
 #include <djinterop/enginelibrary/el_crate_impl.hpp>
 #include <djinterop/enginelibrary/el_database_impl.hpp>
diff --git a/src/djinterop/enginelibrary/el_database_impl.hpp b/src/djinterop/enginelibrary/el_database_impl.hpp
index fa6ca7a..e1e8280 100644
--- a/src/djinterop/enginelibrary/el_database_impl.hpp
+++ b/src/djinterop/enginelibrary/el_database_impl.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_DATABASE_IMPL_HPP
-#define DJINTEROP_ENGINELIBRARY_DATABASE_IMPL_HPP
+#pragma once
 
 #include <sqlite_modern_cpp.h>
 
@@ -62,5 +57,3 @@ private:
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_DATABASE_IMPL_HPP
diff --git a/src/djinterop/enginelibrary/el_storage.cpp b/src/djinterop/enginelibrary/el_storage.cpp
index 2ede572..e481a2f 100644
--- a/src/djinterop/enginelibrary/el_storage.cpp
+++ b/src/djinterop/enginelibrary/el_storage.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <djinterop/enginelibrary/el_storage.hpp>
 
 namespace djinterop
diff --git a/src/djinterop/enginelibrary/el_storage.hpp b/src/djinterop/enginelibrary/el_storage.hpp
index 0d4c652..cb52879 100644
--- a/src/djinterop/enginelibrary/el_storage.hpp
+++ b/src/djinterop/enginelibrary/el_storage.hpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #pragma once
 
 #include <string>
@@ -18,4 +35,4 @@ public:
 };
 
 }  // namespace enginelibrary
-}  // namespace djinterop
\ No newline at end of file
+}  // namespace djinterop
diff --git a/src/djinterop/enginelibrary/el_track_impl.cpp b/src/djinterop/enginelibrary/el_track_impl.cpp
index 3702080..b84347f 100644
--- a/src/djinterop/enginelibrary/el_track_impl.cpp
+++ b/src/djinterop/enginelibrary/el_track_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <cmath>
 
 #include <djinterop/djinterop.hpp>
diff --git a/src/djinterop/enginelibrary/el_track_impl.hpp b/src/djinterop/enginelibrary/el_track_impl.hpp
index 10f4e9f..d06bcff 100644
--- a/src/djinterop/enginelibrary/el_track_impl.hpp
+++ b/src/djinterop/enginelibrary/el_track_impl.hpp
@@ -1,8 +1,21 @@
-#pragma once
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
 
-#if __cplusplus < 201103L && _MSVC_LANG < 201103L
-#error This library needs at least a C++11 compliant compiler
-#endif
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
 
 #include <chrono>
 #include <memory>
diff --git a/src/djinterop/enginelibrary/encode_decode_utils.hpp b/src/djinterop/enginelibrary/encode_decode_utils.hpp
index 17c3adb..8ab72ed 100644
--- a/src/djinterop/enginelibrary/encode_decode_utils.hpp
+++ b/src/djinterop/enginelibrary/encode_decode_utils.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_ENCODE_DECODE_UTILS_HPP
-#define DJINTEROP_ENGINELIBRARY_ENCODE_DECODE_UTILS_HPP
+#pragma once
 
 #include <cstdint>
 #include <cstring>
@@ -168,5 +163,3 @@ inline char* encode_double_be(double value, char* ptr)
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_ENCODE_DECODE_UTILS_HPP
diff --git a/src/djinterop/enginelibrary/performance_data_format.hpp b/src/djinterop/enginelibrary/performance_data_format.hpp
index b65477e..edf9510 100644
--- a/src/djinterop/enginelibrary/performance_data_format.hpp
+++ b/src/djinterop/enginelibrary/performance_data_format.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_PERFORMANCE_DATA_FORMAT_HPP
-#define DJINTEROP_ENGINELIBRARY_PERFORMANCE_DATA_FORMAT_HPP
+#pragma once
 
 #include <cstdint>
 #include <vector>
@@ -108,5 +103,3 @@ struct track_data
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_PERFORMANCE_DATA_FORMAT_HPP
diff --git a/src/djinterop/enginelibrary/schema.hpp b/src/djinterop/enginelibrary/schema.hpp
index 8df9da0..41f0d34 100644
--- a/src/djinterop/enginelibrary/schema.hpp
+++ b/src/djinterop/enginelibrary/schema.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_SCHEMA_HPP
-#define DJINTEROP_ENGINELIBRARY_SCHEMA_HPP
+#pragma once
 
 #include <stdexcept>
 #include <string>
@@ -46,5 +41,3 @@ void create_performance_schema(
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_SCHEMA_HPP
diff --git a/src/djinterop/enginelibrary/schema_1_6_0.hpp b/src/djinterop/enginelibrary/schema_1_6_0.hpp
index 7d6487a..07c3215 100644
--- a/src/djinterop/enginelibrary/schema_1_6_0.hpp
+++ b/src/djinterop/enginelibrary/schema_1_6_0.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_SCHEMA_1_6_0_HPP
-#define DJINTEROP_ENGINELIBRARY_SCHEMA_1_6_0_HPP
+#pragma once
 
 #include <sqlite_modern_cpp.h>
 
@@ -38,5 +33,3 @@ void create_performance_schema_1_6_0(sqlite::database &db);
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_SCHEMA_1_6_0_HPP
diff --git a/src/djinterop/enginelibrary/schema_1_7_1.hpp b/src/djinterop/enginelibrary/schema_1_7_1.hpp
index a6fecc6..57ec062 100644
--- a/src/djinterop/enginelibrary/schema_1_7_1.hpp
+++ b/src/djinterop/enginelibrary/schema_1_7_1.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_SCHEMA_1_7_1_HPP
-#define DJINTEROP_ENGINELIBRARY_SCHEMA_1_7_1_HPP
+#pragma once
 
 #include <sqlite_modern_cpp.h>
 
@@ -38,5 +33,3 @@ void create_performance_schema_1_7_1(sqlite::database &db);
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_SCHEMA_1_7_1_HPP
diff --git a/src/djinterop/enginelibrary/schema_validate_utils.hpp b/src/djinterop/enginelibrary/schema_validate_utils.hpp
index a8613f0..2f830ce 100644
--- a/src/djinterop/enginelibrary/schema_validate_utils.hpp
+++ b/src/djinterop/enginelibrary/schema_validate_utils.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_SCHEMA_VALIDATE_UTILS_HPP
-#define DJINTEROP_ENGINELIBRARY_SCHEMA_VALIDATE_UTILS_HPP
+#pragma once
 
 #include <set>
 #include <string>
@@ -230,5 +225,3 @@ void validate_no_more(
 
 }  // namespace enginelibrary
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_SCHEMA_VALIDATE_UTILS_HPP
diff --git a/src/djinterop/impl/crate_impl.cpp b/src/djinterop/impl/crate_impl.cpp
index 15f88e5..072912b 100644
--- a/src/djinterop/impl/crate_impl.cpp
+++ b/src/djinterop/impl/crate_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <djinterop/database.hpp>
 #include <djinterop/impl/crate_impl.hpp>
 
diff --git a/src/djinterop/impl/crate_impl.hpp b/src/djinterop/impl/crate_impl.hpp
index 7949218..a3f6cb3 100644
--- a/src/djinterop/impl/crate_impl.hpp
+++ b/src/djinterop/impl/crate_impl.hpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #pragma once
 
 #include <string>
diff --git a/src/djinterop/impl/database_impl.cpp b/src/djinterop/impl/database_impl.cpp
index 366ab1c..21e7944 100644
--- a/src/djinterop/impl/database_impl.cpp
+++ b/src/djinterop/impl/database_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <djinterop/impl/database_impl.hpp>
 
 namespace djinterop
diff --git a/src/djinterop/impl/database_impl.hpp b/src/djinterop/impl/database_impl.hpp
index 79faac6..f8a01dd 100644
--- a/src/djinterop/impl/database_impl.hpp
+++ b/src/djinterop/impl/database_impl.hpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #pragma once
 
 #include <string>
diff --git a/src/djinterop/impl/track_impl.cpp b/src/djinterop/impl/track_impl.cpp
index 3863f71..bcade82 100644
--- a/src/djinterop/impl/track_impl.cpp
+++ b/src/djinterop/impl/track_impl.cpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <djinterop/database.hpp>
 #include <djinterop/impl/track_impl.hpp>
 
diff --git a/src/djinterop/impl/track_impl.hpp b/src/djinterop/impl/track_impl.hpp
index 5cd80c7..e59a314 100644
--- a/src/djinterop/impl/track_impl.hpp
+++ b/src/djinterop/impl/track_impl.hpp
@@ -1,3 +1,20 @@
+/*
+    This file is part of libdjinterop.
+
+    libdjinterop is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    libdjinterop is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #pragma once
 
 #include <string>
diff --git a/src/djinterop/impl/util.hpp b/src/djinterop/impl/util.hpp
index 74683d8..ca4bd53 100644
--- a/src/djinterop/impl/util.hpp
+++ b/src/djinterop/impl/util.hpp
@@ -15,12 +15,7 @@
     along with libdjinterop.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#if __cplusplus < 201402L && _MSVC_LANG < 201402L
-#error This library needs at least a C++14 compliant compiler
-#endif
-
-#ifndef DJINTEROP_ENGINELIBRARY_UTIL_HPP
-#define DJINTEROP_ENGINELIBRARY_UTIL_HPP
+#pragma once
 
 #include <boost/optional.hpp>
 #include <boost/utility/string_view.hpp>
@@ -32,5 +27,3 @@ boost::optional<boost::string_view> get_file_extension(
     boost::string_view file_path);
 
 }  // namespace djinterop
-
-#endif  // DJINTEROP_ENGINELIBRARY_UTIL_HPP