refactor: Move underlying to a separate submodule

Author: FrozenLemonTee

src/underlying/impl.cppm

@@ -0,0 +1,37 @@
+module;
+#include <type_traits>
+
+export module mcpplibs.primitives.underlying.impl;
+
+import mcpplibs.primitives.underlying.traits;
+
+export
+template <mcpplibs::primitives::std_underlying_type T>
+struct mcpplibs::primitives::underlying::traits<T> {
+  using value_type = std::remove_cv_t<T>;
+  using rep_type = value_type;
+
+  static constexpr bool enabled = true;
+
+  static constexpr category kind = [] {
+    if constexpr (std_bool<value_type>) {
+      return category::boolean;
+    } else if constexpr (std_char<value_type>) {
+      return category::character;
+    } else if constexpr (std_integer<value_type>) {
+      return category::integer;
+    } else {
+      return category::floating;
+    }
+  }();
+
+  static constexpr rep_type to_rep(value_type value) noexcept { return value; }
+
+  static constexpr value_type from_rep(rep_type value) noexcept {
+    return value;
+  }
+
+  static constexpr bool is_valid_rep(rep_type) noexcept { return true; }
+};
+
+

src/traits/underlying.cppm src/underlying/traits.cppmsrc/traits/underlying.cppm renamed to src/underlying/traits.cppm

@@ -2,7 +2,7 @@ module;
 #include <concepts>
 #include <type_traits>
 
-export module mcpplibs.primitives.traits.underlying;
+export module mcpplibs.primitives.underlying.traits;
 
 export namespace mcpplibs::primitives {
 
@@ -39,38 +39,24 @@ enum class category {
 };
 
 template <typename T> struct traits {
-  static constexpr bool enabled = false;
-};
+  using value_type = void;
+  using rep_type = void;
 
-template <std_underlying_type T> struct traits<T> {
-  using value_type = std::remove_cv_t<T>;
-  using rep_type = value_type;
+  static constexpr bool enabled = false;
 
-  static constexpr bool enabled = true;
+  static constexpr auto kind = static_cast<category>(-1);
 
-  static constexpr category kind = [] {
-    if constexpr (std_bool<value_type>) {
-      return category::boolean;
-    } else if constexpr (std_char<value_type>) {
-      return category::character;
-    } else if constexpr (std_integer<value_type>) {
-      return category::integer;
-    } else {
-      return category::floating;
-    }
-  }();
+  template <typename U> static constexpr rep_type to_rep(U) noexcept {}
 
-  static constexpr rep_type to_rep(value_type value) noexcept { return value; }
+  template <typename U> static constexpr value_type from_rep(U) noexcept {}
 
-  static constexpr value_type from_rep(rep_type value) noexcept {
-    return value;
+  template <typename U> static constexpr bool is_valid_rep(U) noexcept {
+    return false;
   }
-
-  static constexpr bool is_valid_rep(rep_type) noexcept { return true; }
 };
-} // namespace underlying
 
-} // namespace mcpplibs::primitives
+} // namespace underlying
+}
 
 namespace mcpplibs::primitives::underlying::details {
 
@@ -102,8 +88,7 @@ concept has_rep_bridge =
 
 template <typename T>
 concept has_std_rep_type =
-    has_rep_type<T> &&
-    std_underlying_type<typename traits<std::remove_cv_t<T>>::rep_type>;
+    has_rep_type<T> && std_underlying_type<typename traits<std::remove_cv_t<T>>::rep_type>;
 
 template <std_underlying_type T>
 consteval category category_of_std_underlying_type() {
@@ -131,9 +116,11 @@ export namespace mcpplibs::primitives {
 
 template <typename T>
 concept underlying_type =
-    underlying::details::enabled<T> && underlying::details::has_category<T> &&
+    underlying::details::enabled<T> && 
+    underlying::details::has_category<T> &&
     underlying::details::has_rep_bridge<T> &&
     underlying::details::has_std_rep_type<T> &&
     underlying::details::has_consistent_category<T>;
 
 } // namespace mcpplibs::primitives
+

src/underlying/underlying.cppm

@@ -0,0 +1,6 @@
+module;
+
+export module mcpplibs.primitives.underlying;
+
+export import mcpplibs.primitives.underlying.traits;
+export import mcpplibs.primitives.underlying.impl;