refactor: Refine redundant code

Author: FrozenLemonTee

.vscode/compile_commands.json

@@ -0,0 +1 @@
+[

src/conversion/underlying.cppm

@@ -245,6 +245,37 @@ constexpr auto exact_rep_cast(SrcRep value)
   }
 }
 
+template <underlying_type Dest, underlying_type Src, typename RepCaster>
+constexpr auto cast_underlying_value(Src value, RepCaster rep_caster) -> Dest {
+  using src_type = std::remove_cv_t<Src>;
+  using dest_type = std::remove_cv_t<Dest>;
+  using src_rep_type = underlying::traits<src_type>::rep_type;
+  using dest_rep_type = underlying::traits<dest_type>::rep_type;
+
+  auto const source_rep = underlying::traits<src_type>::to_rep(value);
+  auto const target_rep = rep_caster.template operator()<dest_rep_type>(
+      static_cast<src_rep_type>(source_rep));
+  return underlying::traits<dest_type>::from_rep(target_rep);
+}
+
+template <underlying_type Dest, underlying_type Src, typename RepCaster>
+constexpr auto cast_underlying_result(Src value, RepCaster rep_caster)
+    -> cast_result<Dest> {
+  using src_type = std::remove_cv_t<Src>;
+  using dest_type = std::remove_cv_t<Dest>;
+  using src_rep_type = underlying::traits<src_type>::rep_type;
+  using dest_rep_type = underlying::traits<dest_type>::rep_type;
+
+  auto const source_rep = underlying::traits<src_type>::to_rep(value);
+  auto const target_rep = rep_caster.template operator()<dest_rep_type>(
+      static_cast<src_rep_type>(source_rep));
+  if (!target_rep.has_value()) {
+    return std::unexpected(target_rep.error());
+  }
+
+  return underlying::traits<dest_type>::from_rep(*target_rep);
+}
+
 } // namespace mcpplibs::primitives::conversion::details
 
 export namespace mcpplibs::primitives::conversion {
@@ -310,75 +341,42 @@ constexpr auto exact_cast(SrcRep value)
 
 template <underlying_type Dest, underlying_type Src>
 constexpr auto unchecked_cast(Src value) noexcept -> Dest {
-  using src_type = std::remove_cv_t<Src>;
-  using dest_type = std::remove_cv_t<Dest>;
-  using src_rep_type = underlying::traits<src_type>::rep_type;
-  using dest_rep_type = underlying::traits<dest_type>::rep_type;
-
-  auto const source_rep = underlying::traits<src_type>::to_rep(value);
-  auto const target_rep =
-      details::unchecked_rep_cast<dest_rep_type>(static_cast<src_rep_type>(source_rep));
-  return underlying::traits<dest_type>::from_rep(target_rep);
+  return details::cast_underlying_value<Dest>(
+      value, []<typename DestRep, typename SrcRep>(SrcRep rep) {
+        return details::unchecked_rep_cast<DestRep>(rep);
+      });
 }
 
 template <underlying_type Dest, underlying_type Src>
 constexpr auto checked_cast(Src value) -> cast_result<Dest> {
-  using src_type = std::remove_cv_t<Src>;
-  using dest_type = std::remove_cv_t<Dest>;
-  using src_rep_type = underlying::traits<src_type>::rep_type;
-  using dest_rep_type = underlying::traits<dest_type>::rep_type;
-
-  auto const source_rep = underlying::traits<src_type>::to_rep(value);
-  auto const target_rep =
-      details::checked_rep_cast<dest_rep_type>(static_cast<src_rep_type>(source_rep));
-  if (!target_rep.has_value()) {
-    return std::unexpected(target_rep.error());
-  }
-
-  return underlying::traits<dest_type>::from_rep(*target_rep);
+  return details::cast_underlying_result<Dest>(
+      value, []<typename DestRep, typename SrcRep>(SrcRep rep) {
+        return details::checked_rep_cast<DestRep>(rep);
+      });
 }
 
 template <underlying_type Dest, underlying_type Src>
 constexpr auto saturating_cast(Src value) noexcept -> Dest {
-  using src_type = std::remove_cv_t<Src>;
-  using dest_type = std::remove_cv_t<Dest>;
-  using src_rep_type = underlying::traits<src_type>::rep_type;
-  using dest_rep_type = underlying::traits<dest_type>::rep_type;
-
-  auto const source_rep = underlying::traits<src_type>::to_rep(value);
-  auto const target_rep =
-      details::saturating_rep_cast<dest_rep_type>(static_cast<src_rep_type>(source_rep));
-  return underlying::traits<dest_type>::from_rep(target_rep);
+  return details::cast_underlying_value<Dest>(
+      value, []<typename DestRep, typename SrcRep>(SrcRep rep) {
+        return details::saturating_rep_cast<DestRep>(rep);
+      });
 }
 
 template <underlying_type Dest, underlying_type Src>
 constexpr auto truncating_cast(Src value) noexcept -> Dest {
-  using src_type = std::remove_cv_t<Src>;
-  using dest_type = std::remove_cv_t<Dest>;
-  using src_rep_type = underlying::traits<src_type>::rep_type;
-  using dest_rep_type = underlying::traits<dest_type>::rep_type;
-
-  auto const source_rep = underlying::traits<src_type>::to_rep(value);
-  auto const target_rep =
-      details::truncating_rep_cast<dest_rep_type>(static_cast<src_rep_type>(source_rep));
-  return underlying::traits<dest_type>::from_rep(target_rep);
+  return details::cast_underlying_value<Dest>(
+      value, []<typename DestRep, typename SrcRep>(SrcRep rep) {
+        return details::truncating_rep_cast<DestRep>(rep);
+      });
 }
 
 template <underlying_type Dest, underlying_type Src>
 constexpr auto exact_cast(Src value) -> cast_result<Dest> {
-  using src_type = std::remove_cv_t<Src>;
-  using dest_type = std::remove_cv_t<Dest>;
-  using src_rep_type = underlying::traits<src_type>::rep_type;
-  using dest_rep_type = underlying::traits<dest_type>::rep_type;
-
-  auto const source_rep = underlying::traits<src_type>::to_rep(value);
-  auto const target_rep =
-      details::exact_rep_cast<dest_rep_type>(static_cast<src_rep_type>(source_rep));
-  if (!target_rep.has_value()) {
-    return std::unexpected(target_rep.error());
-  }
-
-  return underlying::traits<dest_type>::from_rep(*target_rep);
+  return details::cast_underlying_result<Dest>(
+      value, []<typename DestRep, typename SrcRep>(SrcRep rep) {
+        return details::exact_rep_cast<DestRep>(rep);
+      });
 }
 
 } // namespace mcpplibs::primitives::conversion