diff --git a/src/share/manipulator/manipulators/basic/basic.hpp b/src/share/manipulator/manipulators/basic/basic.hpp
index fe58796b5..648657cb3 100644
--- a/src/share/manipulator/manipulators/basic/basic.hpp
+++ b/src/share/manipulator/manipulators/basic/basic.hpp
@@ -40,7 +40,7 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
           if (value.is_object()) {
             try {
               to_ = std::vector<to_event_definition>{
-                  value.get<to_event_definition>(),
+                  to_event_definition(value),
               };
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -48,7 +48,9 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
 
           } else if (value.is_array()) {
             try {
-              to_ = value.get<std::vector<to_event_definition>>();
+              for (const auto& j : value) {
+                to_.push_back(to_event_definition(j));
+              }
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
             }
@@ -61,7 +63,7 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
           if (value.is_object()) {
             try {
               to_after_key_up_ = std::vector<to_event_definition>{
-                  value.get<to_event_definition>(),
+                  to_event_definition(value),
               };
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -69,7 +71,9 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
 
           } else if (value.is_array()) {
             try {
-              to_after_key_up_ = value.get<std::vector<to_event_definition>>();
+              for (const auto& j : value) {
+                to_after_key_up_.push_back(to_event_definition(j));
+              }
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
             }
@@ -82,7 +86,7 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
           if (value.is_object()) {
             try {
               to_if_alone_ = std::vector<to_event_definition>{
-                  value.get<to_event_definition>(),
+                  to_event_definition(value),
               };
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -90,7 +94,9 @@ class basic final : public base, public pqrs::dispatcher::extra::dispatcher_clie
 
           } else if (value.is_array()) {
             try {
-              to_if_alone_ = value.get<std::vector<to_event_definition>>();
+              for (const auto& j : value) {
+                to_if_alone_.push_back(to_event_definition(j));
+              }
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
             }
diff --git a/src/share/manipulator/manipulators/basic/simultaneous_options.hpp b/src/share/manipulator/manipulators/basic/simultaneous_options.hpp
index 076c13c9e..6ca9c4cfd 100644
--- a/src/share/manipulator/manipulators/basic/simultaneous_options.hpp
+++ b/src/share/manipulator/manipulators/basic/simultaneous_options.hpp
@@ -67,7 +67,7 @@ class simultaneous_options final {
         if (value.is_object()) {
           try {
             to_after_key_up_ = std::vector<to_event_definition>{
-                value.get<to_event_definition>(),
+                to_event_definition(value),
             };
           } catch (const pqrs::json::unmarshal_error& e) {
             throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -75,7 +75,9 @@ class simultaneous_options final {
 
         } else if (value.is_array()) {
           try {
-            to_after_key_up_ = value.get<std::vector<to_event_definition>>();
+            for (const auto& j : value) {
+              to_after_key_up_.push_back(to_event_definition(j));
+            }
           } catch (const pqrs::json::unmarshal_error& e) {
             throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
           }
diff --git a/src/share/manipulator/manipulators/basic/to_delayed_action.hpp b/src/share/manipulator/manipulators/basic/to_delayed_action.hpp
index 5da5033b1..e6c5dca01 100644
--- a/src/share/manipulator/manipulators/basic/to_delayed_action.hpp
+++ b/src/share/manipulator/manipulators/basic/to_delayed_action.hpp
@@ -21,7 +21,7 @@ class to_delayed_action final : public pqrs::dispatcher::extra::dispatcher_clien
           if (value.is_object()) {
             try {
               to_if_invoked_ = std::vector<to_event_definition>{
-                  value.get<to_event_definition>(),
+                  to_event_definition(value),
               };
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -29,7 +29,9 @@ class to_delayed_action final : public pqrs::dispatcher::extra::dispatcher_clien
 
           } else if (value.is_array()) {
             try {
-              to_if_invoked_ = value.get<std::vector<to_event_definition>>();
+              for (const auto& j : value) {
+                to_if_invoked_.push_back(to_event_definition(j));
+              }
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
             }
@@ -42,7 +44,7 @@ class to_delayed_action final : public pqrs::dispatcher::extra::dispatcher_clien
           if (value.is_object()) {
             try {
               to_if_canceled_ = std::vector<to_event_definition>{
-                  value.get<to_event_definition>(),
+                  to_event_definition(value),
               };
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
@@ -50,7 +52,9 @@ class to_delayed_action final : public pqrs::dispatcher::extra::dispatcher_clien
 
           } else if (value.is_array()) {
             try {
-              to_if_canceled_ = value.get<std::vector<to_event_definition>>();
+              for (const auto& j : value) {
+                to_if_canceled_.push_back(to_event_definition(j));
+              }
             } catch (const pqrs::json::unmarshal_error& e) {
               throw pqrs::json::unmarshal_error(fmt::format("`{0}` entry error: {1}", key, e.what()));
             }
diff --git a/src/share/manipulator/manipulators/basic/to_if_held_down.hpp b/src/share/manipulator/manipulators/basic/to_if_held_down.hpp
index a658d4661..0ebe1f120 100644
--- a/src/share/manipulator/manipulators/basic/to_if_held_down.hpp
+++ b/src/share/manipulator/manipulators/basic/to_if_held_down.hpp
@@ -17,11 +17,13 @@ class to_if_held_down final : public pqrs::dispatcher::extra::dispatcher_client
     try {
       if (json.is_object()) {
         to_ = std::vector<to_event_definition>{
-            json.get<to_event_definition>(),
+            to_event_definition(json),
         };
 
       } else if (json.is_array()) {
-        to_ = json.get<std::vector<to_event_definition>>();
+        for (const auto& j : json) {
+          to_.push_back(to_event_definition(j));
+        }
 
       } else {
         throw pqrs::json::unmarshal_error(fmt::format("json must be object or array, but is `{0}`", pqrs::json::dump_for_error_message(json)));
diff --git a/src/share/manipulator/types/to_event_definition.hpp b/src/share/manipulator/types/to_event_definition.hpp
index 3b22e22a1..43b6c85d0 100644
--- a/src/share/manipulator/types/to_event_definition.hpp
+++ b/src/share/manipulator/types/to_event_definition.hpp
@@ -9,10 +9,71 @@ namespace krbn {
 namespace manipulator {
 class to_event_definition final {
 public:
-  to_event_definition(void) : lazy_(false),
-                              repeat_(true),
-                              halt_(false),
-                              hold_down_milliseconds_(0) {
+  to_event_definition(void)
+      : lazy_(false),
+        repeat_(true),
+        halt_(false),
+        hold_down_milliseconds_(0) {
+  }
+
+  to_event_definition(const nlohmann::json& json)
+      : to_event_definition() {
+    pqrs::json::requires_object(json, "json");
+
+    for (const auto& [key, value] : json.items()) {
+      if (event_definition_.handle_json(key, value, json)) {
+        // Do nothing
+
+      } else if (key == "modifiers") {
+        try {
+          modifiers_ = modifier_definition::make_modifiers(value);
+        } catch (const pqrs::json::unmarshal_error& e) {
+          throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
+        }
+
+      } else if (key == "lazy") {
+        pqrs::json::requires_boolean(value, "`" + key + "`");
+
+        lazy_ = value.get<bool>();
+
+      } else if (key == "repeat") {
+        pqrs::json::requires_boolean(value, "`" + key + "`");
+
+        repeat_ = value.get<bool>();
+
+      } else if (key == "halt") {
+        pqrs::json::requires_boolean(value, "`" + key + "`");
+
+        halt_ = value.get<bool>();
+
+      } else if (key == "hold_down_milliseconds" ||
+                 key == "held_down_milliseconds") {
+        pqrs::json::requires_number(value, "`" + key + "`");
+
+        hold_down_milliseconds_ = std::chrono::milliseconds(value.get<int>());
+
+      } else {
+        throw pqrs::json::unmarshal_error(fmt::format("unknown key `{0}` in `{1}`", key, pqrs::json::dump_for_error_message(json)));
+      }
+    }
+
+    // ----------------------------------------
+
+    switch (event_definition_.get_type()) {
+      case event_definition::type::momentary_switch_event:
+      case event_definition::type::shell_command:
+      case event_definition::type::select_input_source:
+      case event_definition::type::set_variable:
+      case event_definition::type::set_notification_message:
+      case event_definition::type::mouse_key:
+      case event_definition::type::sticky_modifier:
+      case event_definition::type::software_function:
+        break;
+
+      case event_definition::type::none:
+      case event_definition::type::any:
+        throw pqrs::json::unmarshal_error(fmt::format("event type is invalid: `{0}`", pqrs::json::dump_for_error_message(json)));
+    }
   }
 
   virtual ~to_event_definition(void) {
@@ -110,64 +171,5 @@ class to_event_definition final {
   bool halt_;
   std::chrono::milliseconds hold_down_milliseconds_;
 };
-
-inline void from_json(const nlohmann::json& json, to_event_definition& d) {
-  pqrs::json::requires_object(json, "json");
-
-  for (const auto& [key, value] : json.items()) {
-    if (d.get_event_definition().handle_json(key, value, json)) {
-      // Do nothing
-
-    } else if (key == "modifiers") {
-      try {
-        d.set_modifiers(modifier_definition::make_modifiers(value));
-      } catch (const pqrs::json::unmarshal_error& e) {
-        throw pqrs::json::unmarshal_error(fmt::format("`{0}` error: {1}", key, e.what()));
-      }
-
-    } else if (key == "lazy") {
-      pqrs::json::requires_boolean(value, "`" + key + "`");
-
-      d.set_lazy(value.get<bool>());
-
-    } else if (key == "repeat") {
-      pqrs::json::requires_boolean(value, "`" + key + "`");
-
-      d.set_repeat(value.get<bool>());
-
-    } else if (key == "halt") {
-      pqrs::json::requires_boolean(value, "`" + key + "`");
-
-      d.set_halt(value.get<bool>());
-
-    } else if (key == "hold_down_milliseconds" ||
-               key == "held_down_milliseconds") {
-      pqrs::json::requires_number(value, "`" + key + "`");
-
-      d.set_hold_down_milliseconds(std::chrono::milliseconds(value.get<int>()));
-
-    } else {
-      throw pqrs::json::unmarshal_error(fmt::format("unknown key `{0}` in `{1}`", key, pqrs::json::dump_for_error_message(json)));
-    }
-  }
-
-  // ----------------------------------------
-
-  switch (d.get_event_definition().get_type()) {
-    case event_definition::type::momentary_switch_event:
-    case event_definition::type::shell_command:
-    case event_definition::type::select_input_source:
-    case event_definition::type::set_variable:
-    case event_definition::type::set_notification_message:
-    case event_definition::type::mouse_key:
-    case event_definition::type::sticky_modifier:
-    case event_definition::type::software_function:
-      break;
-
-    case event_definition::type::none:
-    case event_definition::type::any:
-      throw pqrs::json::unmarshal_error(fmt::format("event type is invalid: `{0}`", pqrs::json::dump_for_error_message(json)));
-  }
-}
 } // namespace manipulator
 } // namespace krbn
diff --git a/tests/src/manipulator_types/src/errors_test.hpp b/tests/src/manipulator_types/src/errors_test.hpp
index 9e9759519..0e1c2b8e2 100644
--- a/tests/src/manipulator_types/src/errors_test.hpp
+++ b/tests/src/manipulator_types/src/errors_test.hpp
@@ -20,7 +20,7 @@ void handle_json(const nlohmann::json& json) {
   } else if (c == "modifier_definition") {
     krbn::manipulator::modifier_definition::make_modifiers(json.at("input"));
   } else if (c == "to_event_definition") {
-    json.at("input").get<krbn::manipulator::to_event_definition>();
+    krbn::manipulator::to_event_definition(json.at("input"));
   } else {
     expect(false);
   }