add get_members_fieldname_map.

171930433 · Jun 19, 2024 · 0042719 · 0042719
1 parent cb91e08
commit 0042719
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Showing 2 changed files with 34 additions and 17 deletions.
diff --git a/include/ylt/standalone/iguana/pb_util.hpp b/include/ylt/standalone/iguana/pb_util.hpp
@@ -54,25 +54,20 @@ struct base_impl : public base {
   }
 
   std::any get_field_any(std::string_view name) const override {
-    static constexpr auto map = iguana::get_members<T>();
-    std::any result;
-    for (auto const& [no, field] : map) {
-      if (result.has_value()) {
-        break;
-      }
+    static constexpr auto map = iguana::get_members_fieldname_map<T>();
 
-      std::visit(
-          [&](auto val) {
-            if (val.field_name == name) {
-              auto const offset = member_offset((T*)this, val.member_ptr);
-              auto const ptr = (((char*)this) + offset);
-              using value_type = typename decltype(val)::value_type;
-              result = *((value_type*)ptr);
-            }
-          },
-          field);
+    if (map.find(name) == map.end()) {
+      return {};
     }
-    return result;
+
+    return std::visit(
+        [&](auto val) {
+          auto const offset = member_offset((T*)this, val.member_ptr);
+          auto const ptr = (((char*)this) + offset);
+          using value_type = typename decltype(val)::value_type;
+          return std::any{*((value_type*)ptr)};
+        },
+        map.at(name));
   }
 
   iguana::detail::field_info get_field_info(std::string_view name) override {

diff --git a/include/ylt/standalone/iguana/reflection.hpp b/include/ylt/standalone/iguana/reflection.hpp
@@ -874,6 +874,13 @@ constexpr auto inline get_members_impl(Tuple &&tp, std::index_sequence<I...>) {
        T{std::in_place_index<I>, std::move(std::get<I>(tp))}}...};
 }
 
+template <typename T, size_t Size, typename Tuple, size_t... I>
+constexpr auto inline get_members_fieldname_map_impl(Tuple &&tp, std::index_sequence<I...>) {
+  return frozen::unordered_map<frozen::string, T, sizeof...(I)>{
+      {std::get<I>(tp).field_name,
+       T{std::in_place_index<I>, std::move(std::get<I>(tp))}}...};
+}
+
 template <typename T>
 constexpr size_t count_variant_size() {
   if constexpr (is_variant<T>::value) {
@@ -912,6 +919,21 @@ constexpr inline auto get_members() {
   }
 }
 
+template <typename T>
+constexpr inline auto get_members_fieldname_map() {
+  if constexpr (is_reflection_v<T> || is_custom_reflection_v<T>) {
+    constexpr auto tp = get_members_tuple<T>();
+    using Tuple = std::decay_t<decltype(tp)>;
+    using value_type = typename field_type_t<Tuple>::value_type;
+    constexpr auto Size = tuple_type_count<Tuple>();
+    return get_members_fieldname_map_impl<value_type, Size>(tp,
+                                              std::make_index_sequence<Size>{});
+  }
+  else {
+    static_assert(!sizeof(T), "expected reflection or custom reflection");
+  }
+}
+
 #define REFLECTION(STRUCT_NAME, ...)                                    \
   MAKE_META_DATA(STRUCT_NAME, #STRUCT_NAME, GET_ARG_COUNT(__VA_ARGS__), \
                  __VA_ARGS__)