From 8f2427996e421cd49e663a29a78e954af475b6ec Mon Sep 17 00:00:00 2001
From: BlackMATov <blackmat@mail.ru>
Date: Tue, 6 Jul 2021 04:16:15 +0700
Subject: [PATCH] instance and cinstance classes

---
 headers/meta.hpp/meta.hpp          |  1 +
 headers/meta.hpp/meta_instance.hpp | 99 ++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+)
 create mode 100644 headers/meta.hpp/meta_instance.hpp

diff --git a/headers/meta.hpp/meta.hpp b/headers/meta.hpp/meta.hpp
index 5a4b00a..125d059 100644
--- a/headers/meta.hpp/meta.hpp
+++ b/headers/meta.hpp/meta.hpp
@@ -8,6 +8,7 @@
 
 #include "meta_fwd.hpp"
 
+#include "meta_instance.hpp"
 #include "meta_value.hpp"
 
 #include "meta_registry.hpp"
diff --git a/headers/meta.hpp/meta_instance.hpp b/headers/meta.hpp/meta_instance.hpp
new file mode 100644
index 0000000..dd01c77
--- /dev/null
+++ b/headers/meta.hpp/meta_instance.hpp
@@ -0,0 +1,99 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "meta_fwd.hpp"
+
+#include "meta_value.hpp"
+
+namespace meta_hpp
+{
+    class instance;
+    class cinstance;
+}
+
+namespace meta_hpp
+{
+    class instance {
+    public:
+        instance() = delete;
+
+        instance(instance&&) = default;
+        instance(const instance&) = default;
+
+        instance& operator=(instance&&) = default;
+        instance& operator=(const instance&) = default;
+
+        template < typename T
+                 , typename = std::enable_if_t<!std::is_same_v<T, value>>
+                 , typename = std::enable_if_t<!std::is_same_v<T, instance>>
+                 , typename = std::enable_if_t<!std::is_same_v<T, cinstance>> >
+        instance(T& v)
+        : data_{std::addressof(v)}
+        , fid_{get_type_family_id<T>()} {}
+
+        instance(value& v)
+        : data_{v.data()}
+        , fid_{v.fid()} {}
+
+        void* data() noexcept {
+            return data_;
+        }
+
+        const void* data() const noexcept {
+            return data_;
+        }
+
+        family_id fid() const noexcept {
+            return fid_;
+        }
+    private:
+        void* data_{};
+        family_id fid_{};
+    };
+}
+
+namespace meta_hpp
+{
+    class cinstance {
+    public:
+        cinstance() = delete;
+
+        cinstance(cinstance&&) = default;
+        cinstance(const cinstance&) = default;
+
+        cinstance& operator=(cinstance&&) = default;
+        cinstance& operator=(const cinstance&) = default;
+
+        template < typename T
+                 , typename = std::enable_if_t<!std::is_same_v<T, value>>
+                 , typename = std::enable_if_t<!std::is_same_v<T, instance>>
+                 , typename = std::enable_if_t<!std::is_same_v<T, cinstance>> >
+        cinstance(const T& data)
+        : data_{std::addressof(data)}
+        , fid_{get_type_family_id<T>()} {}
+
+        cinstance(const value& v)
+        : data_{v.data()}
+        , fid_{v.fid()} {}
+
+        cinstance(const instance& v)
+        : data_{v.data()}
+        , fid_{v.fid()} {}
+
+        const void* data() const noexcept {
+            return data_;
+        }
+
+        family_id fid() const noexcept {
+            return fid_;
+        }
+    private:
+        const void* data_{};
+        family_id fid_{};
+    };
+}