From cc8f5ebc273ee0e24717468864ad16130ff6d192 Mon Sep 17 00:00:00 2001
From: Christos Houtouridis <houtouridis.ch@gmail.com>
Date: Tue, 23 Oct 2018 00:50:03 +0300
Subject: [PATCH] impl: Add first files (untested)

---
 include/utl/impl/concepts.h | 46 +++++++++++++++++++++++++++++++++++
 include/utl/impl/crtp.h     | 48 +++++++++++++++++++++++++++++++++++++
 include/utl/impl/version.h  | 40 +++++++++++++++++++++++++++++++
 3 files changed, 134 insertions(+)
 create mode 100755 include/utl/impl/concepts.h
 create mode 100755 include/utl/impl/crtp.h
 create mode 100755 include/utl/impl/version.h

diff --git a/include/utl/impl/concepts.h b/include/utl/impl/concepts.h
new file mode 100755
index 0000000..b597c05
--- /dev/null
+++ b/include/utl/impl/concepts.h
@@ -0,0 +1,46 @@
+/*!
+ * \file   /utl/impl/concepts.h
+ * \brief  Concept support header
+ *
+ * Copyright (C) 2018 Christos Choutouridis
+ *
+ * This program 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.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#ifndef __utl_impl_concepts_h__
+#define __utl_impl_concepts_h__
+
+#include <utl/impl/version.h>
+
+/*!
+ * utl inner concept preprecessor flag
+ * \defgroup crtp
+ * \ingroup impl
+ */
+//!@{
+#if defined __cpp_concepts
+#define _utl_have_concepts (1)
+#endif
+
+/*!
+ * requires keyword wraper
+ */
+#if defined _utl_have_concepts
+   #define _requires(_r_) requires (_r_)
+#else
+   #define _requires(_r_)
+#endif
+
+//!@}
+#endif /* __utl_impl_concepts_h__ */
diff --git a/include/utl/impl/crtp.h b/include/utl/impl/crtp.h
new file mode 100755
index 0000000..9258a87
--- /dev/null
+++ b/include/utl/impl/crtp.h
@@ -0,0 +1,48 @@
+/*!
+ * \file   /utl/impl/crtp.h
+ * \brief  CRTP idiom support header
+ *
+ * Copyright (C) 2018 Christos Choutouridis
+ *
+ * This program 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.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#ifndef __utl_impl_crtp_h__
+#define __utl_impl_crtp_h__
+
+#include <utl/impl/version.h>
+
+/*!
+ * \defgroup crtp   CRTP idiom support header
+ * \ingroup  impl
+ *
+ *  utl supports both CRTP idiom and dynamic polymorphism. By default
+ *  CRTP is the preferred way. If the user need virtuals then instead of
+ *  CRTP type, the \ref virtual_tag can passed to base class. The rest
+ *  will handled by utl automatically.
+ */
+//!@{
+namespace utl {
+   //! CRTP support tag type
+   struct crtp_tag { };
+   //! virtual support tag type
+   struct virtual_tag { };
+
+   //! \def CRTP boilerplate lines
+   #define _CRTP_IMPL(T) \
+      constexpr T& impl() { return *static_cast<T*>(this); } \
+      constexpr const T& impl() const { return *static_cast<const T*>(this); }
+}
+//!@}
+#endif /* __utl_impl_crtp_h__ */
diff --git a/include/utl/impl/version.h b/include/utl/impl/version.h
new file mode 100755
index 0000000..a15b6f5
--- /dev/null
+++ b/include/utl/impl/version.h
@@ -0,0 +1,40 @@
+/*!
+ * \file   /utl/impl/version.h
+ * \brief  version and cpp version check
+ *
+ * Copyright (C) 2018 Christos Choutouridis
+ *
+ * This program 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.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#ifndef __utl_impl_crtp_h__
+#define __utl_impl_crtp_h__
+
+//!\defgroup version version
+//! Definitions of the utl version
+//!\ingroup impl
+
+#define UTL_VERSION       "0.0.0"
+#define UTL_VERSION_MAJOR  0
+#define UTL_VERSION_MINOR  0
+#define UTL_VERSION_PATCH  0
+#define UTL_VERSION_VALUE ( (UTL_VERSION_MAJOR * 10000) \
+                          + (UTL_VERSION_MINOR * 100)   \
+                          + UTL_VERSION_PATCH)
+
+#if __cplusplus < 201103L
+#error "Sorry. uTL requires C++11"
+#endif
+
+#endif /* __utl_impl_crtp_h__ */