refactor: Rename kind to code in error handling structures

Author: FrozenLemonTee

src/operations/dispatcher.cppm

@@ -132,7 +132,7 @@ constexpr auto dispatch(Lhs const &lhs, Rhs const &rhs)
       !underlying::traits<typename meta::rhs_value_type>::is_valid_rep(
           rhs_rep_raw)) {
     policy::error::request<common_rep> request{};
-    request.kind = policy::error::kind::domain_error;
+    request.code = policy::error::kind::domain_error;
     request.reason = "invalid underlying representation";
     return runtime::resolve_error<typename meta::error_policy, OpTag,
                                   common_rep, ErrorPayload>(request);

src/operations/invoker.cppm

@@ -27,7 +27,7 @@ constexpr auto make_error(policy::error::kind kind, char const *reason,
     -> policy::value::decision<CommonRep> {
   policy::value::decision<CommonRep> out{};
   out.has_value = false;
-  out.error.kind = kind;
+  out.error.code = kind;
   out.error.reason = reason;
   out.error.lhs_value = lhs;
   out.error.rhs_value = rhs;
@@ -385,7 +385,7 @@ struct op_binding {
       -> policy::value::decision<CommonRep> {
     policy::value::decision<CommonRep> out{};
     out.has_value = false;
-    out.error.kind = policy::error::kind::unspecified;
+    out.error.code = policy::error::kind::unspecified;
     out.error.reason = "operation binding is not implemented";
     return out;
   }

src/policy/handler.cppm

@@ -28,7 +28,7 @@ enum class kind : unsigned char {
 };
 
 template <typename CommonRep> struct request {
-  kind kind = kind::none;
+  kind code = kind::none;
   std::string_view reason{};
   std::optional<CommonRep> lhs_value{};
   std::optional<CommonRep> rhs_value{};

src/policy/impl.cppm

@@ -280,7 +280,7 @@ struct error::handler<error::expected, OpTag, CommonRep, ErrorPayload> {
 
   static constexpr auto resolve(request_type const &request) -> result_type {
     return std::unexpected(
-        details::to_error_payload<ErrorPayload>(request.kind));
+        details::to_error_payload<ErrorPayload>(request.code));
   }
 };