types/description: add trivial type categorisation enums

CMakeLists.txt

@@ -399,6 +399,8 @@ list (
     typeidx.hpp
     types/bits.hpp
     types/comparator.hpp
+    types/description.cpp
+    types/description.hpp
     types.hpp
     types/string.cpp
     types/string.hpp

types/description.cpp

@@ -0,0 +1,42 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright 2018 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "description.hpp"
+
+#include "../debug.hpp"
+
+
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+util::types::operator<< (std::ostream &os, util::types::category val)
+{
+    switch (val) {
+    case category::NONE:        return os << "NONE";
+    case category::UNSIGNED:    return os << "UNSIGNED";
+    case category::SIGNED:      return os << "SIGNED";
+    case category::REAL:        return os << "REAL";
+    }
+
+    unreachable ();
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+std::ostream&
+util::types::operator<< (std::ostream &os, util::types::description val)
+{
+    return os << "{ category: " << val.category << ", width: " << val.width << " }";
+}

types/description.hpp

@@ -0,0 +1,77 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright 2018 Danny Robson <danny@nerdcruft.net>
+ */
+
+#pragma once
+
+#include "../std.hpp"
+
+#include <cstddef>
+#include <type_traits>
+
+namespace util::types {
+    //-------------------------------------------------------------------------
+    enum class category {
+        NONE,
+        UNSIGNED,
+        SIGNED,
+        REAL,
+    };
+
+    //-------------------------------------------------------------------------
+    struct description {
+        enum category category;
+        std::size_t width;
+    };
+
+
+    //-------------------------------------------------------------------------
+    template <typename T>
+    struct category_traits;
+
+    template <> struct category_traits<u08> : public std::integral_constant<category,category::UNSIGNED> {};
+    template <> struct category_traits<u16> : public std::integral_constant<category,category::UNSIGNED> {};
+    template <> struct category_traits<u32> : public std::integral_constant<category,category::UNSIGNED> {};
+    template <> struct category_traits<u64> : public std::integral_constant<category,category::UNSIGNED> {};
+
+    template <> struct category_traits<i08> : public std::integral_constant<category,category::SIGNED> {};
+    template <> struct category_traits<i16> : public std::integral_constant<category,category::SIGNED> {};
+    template <> struct category_traits<i32> : public std::integral_constant<category,category::SIGNED> {};
+    template <> struct category_traits<i64> : public std::integral_constant<category,category::SIGNED> {};
+
+    template <> struct category_traits<f32> : public std::integral_constant<category,category::REAL> {};
+    template <> struct category_traits<f64> : public std::integral_constant<category,category::REAL> {};
+
+    template <typename T>
+    constexpr auto category_traits_v = category_traits<T>::value;
+
+
+    //-------------------------------------------------------------------------
+    template <typename T>
+    constexpr description
+    make_description (void) noexcept
+    {
+        return {
+            .category = category_traits_v<T>,
+            .width = sizeof (T)
+        };
+    }
+}
+
+#include <iosfwd>
+namespace util::types {
+    std::ostream& operator<< (std::ostream&, category);
+    std::ostream& operator<< (std::ostream&, description);
+}