diff --git a/include/basic_type_check.hpp b/include/basic_type_check.hpp
index d8d7eef..5ddd838 100644
--- a/include/basic_type_check.hpp
+++ b/include/basic_type_check.hpp
@@ -6,7 +6,9 @@
 namespace type_check {
 
 // IN PROGRESS: modifiers ??
-nodes::TypeCheckResult type_check_literal(const nodes::Literal &literal,
-                                          SourcesManager &sources_manager);
+nodes::TypeCheckResult
+type_check_literal(const nodes::Literal &literal,
+                   SourcesManager &sources_manager,
+                   nodes::MaybeTypeProxy expected_type);
 
 } // namespace type_check
diff --git a/include/expression_type_check.hpp b/include/expression_type_check.hpp
index caa6ceb..1bec090 100644
--- a/include/expression_type_check.hpp
+++ b/include/expression_type_check.hpp
@@ -11,21 +11,22 @@
 
 namespace type_check {
 
+// TODO: make context stack o top of RAII
 class State {
 public:
   bool insert_variable(const std::string &name, nodes::TypeProxy type) {
-    if (contexts_.size() == 0) {
+    if (contexts_.empty()) {
       error_handling::handle_general_error(
           "Insert variable into contexts_ with zero elements in State");
     }
 
-    return contexts_.back().insert({name, type}).second;
+    return contexts_.back().variables.insert({name, type}).second;
   }
 
-  std::optional<nodes::TypeProxy> find_variable(const std::string &name) {
+  nodes::MaybeTypeProxy find_variable(const std::string &name) {
     for (ssize_t i = contexts_.size(); i >= 0; --i) {
-      auto iter = contexts_[i].find(name);
-      if (iter != contexts_[i].end()) {
+      auto iter = contexts_[i].variables.find(name);
+      if (iter != contexts_[i].variables.end()) {
         return iter->second;
       }
     }
@@ -33,84 +34,136 @@ public:
     return std::nullopt;
   }
 
-  void enter_context() { contexts_.emplace_back(); }
+  void enter_context(const nodes::Node& node) { contexts_.emplace_back(node); }
 
-  void exit_context() {
-    if (contexts_.size() == 0) {
+  // returns brought type, return type is merged with next context or with
+  // brought type in last context
+  nodes::MaybeTypeProxy exit_context() {
+    if (contexts_.empty()) {
       error_handling::handle_general_error(
           "Pop from contexts_ with zero elements in State");
     }
 
+    const auto brought_type = contexts_.back().brought_type;
+    const auto returned_type = contexts_.back().returned_type;
     contexts_.pop_back();
+
+    if (contexts_.empty()) {
+      // TODO: merge returned and brought types
+    } else {
+      // TODO: merge to previous
+    }
+
+    return brought_type;
+  }
+
+  bool bring_type(nodes::TypeProxy type) {
+    if (contexts_.empty()) {
+      error_handling::handle_general_error(
+          "Set brought type to contexts_ with zero elements in State");
+    }
+    auto &brought_type = contexts_.back().brought_type;
+    if (brought_type.has_value() &&) {
+      // TODO
+      return false;
+    }
+    brought_type = type;
+    return true;
+  }
+
+  bool return_type(nodes::TypeProxy type) {
+    if (contexts_.empty()) {
+      error_handling::handle_general_error(
+          "Set returned type to contexts_ with zero elements in State");
+    }
+    auto &returned_type = contexts_.back().returned_type;
+    if (returned_type.has_value() &&) {
+      // TODO
+      return false;
+    }
+    returned_type = type;
+    return true;
   }
 
 public:
-  std::optional<nodes::TypeProxy> brought_type;
-  std::optional<nodes::TypeProxy> returned_type;
+  class Context {
+  public:
+    Context(const nodes::Node& node) : node(node) {}
+
+  public:
+    nodes::MaybeTypeProxy brought_type;
+    nodes::MaybeTypeProxy returned_type;
+    std::unordered_map<std::string, nodes::TypeProxy> variables;
+    const nodes::Node& node;
+  };
 
 private:
-  std::vector<std::unordered_map<std::string, nodes::TypeProxy>> contexts_ = {
-      {}};
+  std::vector<Context> contexts_ = {{}};
+};
+
+class Arguments {
+public:
+    nodes::MaybeTypeProxy expected_type = {};  
 };
 
 nodes::TypeCheckResult
 type_check_expression(const nodes::Expression &expression,
-                      SourcesManager &sources_manager, State &state);
+                      SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 // --- flow control
 
 nodes::TypeCheckResult type_check_match(const nodes::Match &expression,
                                         SourcesManager &sources_manager,
-                                        State &state);
+                                        State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult type_check_condition(const nodes::Condition &expression,
                                             SourcesManager &sources_manager,
-                                            State &state);
+                                            State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult type_check_loop(const nodes::Loop &expression,
                                        SourcesManager &sources_manager,
-                                       State &state);
+                                       State &state, const Arguments& arguments = {});
 
 // --- containers
 
 nodes::TypeCheckResult type_check_container(const nodes::Container &expression,
                                             SourcesManager &sources_manager,
-                                            State &state);
+                                            State &state, const Arguments& arguments = {});
 
 // --- modifiers
 
 nodes::TypeCheckResult type_check_return(const nodes::Return &expression,
                                          SourcesManager &sources_manager,
-                                         State &state);
+                                         State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult
 type_check_name_definition(const nodes::NameDefinition &expression,
-                           SourcesManager &sources_manager, State &state);
+                           SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult type_check_access(const nodes::Access &expression,
                                          SourcesManager &sources_manager,
-                                         State &state);
+                                         State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult
 type_check_loop_control(const nodes::LoopControl &expression,
-                        SourcesManager &sources_manager, State &state);
+                        SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult
 type_check_modifier_expression(const nodes::ModifierExpression &expression,
-                               SourcesManager &sources_manager, State &state);
+                               SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 // --- other
 
 nodes::TypeCheckResult
 type_check_name_expression(const nodes::NameExpression &expression,
-                           SourcesManager &sources_manager, State &state);
+                           SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult
 type_check_constructor(const nodes::Constructor &expression,
-                       SourcesManager &sources_manager, State &state);
+                       SourcesManager &sources_manager, State &state, const Arguments& arguments = {});
 
 nodes::TypeCheckResult type_check_lambda(const nodes::Lambda &expression,
                                          SourcesManager &sources_manager,
-                                         State &state);
+                                         State &state, const Arguments& arguments = {});
 
 } // namespace type_check
diff --git a/include/nodes/type_nodes.hpp b/include/nodes/type_nodes.hpp
index e3cb225..dbc82cb 100644
--- a/include/nodes/type_nodes.hpp
+++ b/include/nodes/type_nodes.hpp
@@ -26,6 +26,8 @@ public:
 
   const Type *get() const;
 
+  bool operator==(const TypeProxy& other) const;
+
 private:
   TypeProxy(TypeStorage &type_storage, size_t id)
       : type_storage_(&type_storage), id_(id) {}
@@ -35,6 +37,8 @@ private:
   size_t id_;
 };
 
+using MaybeTypeProxy = std::optional<TypeProxy>;
+
 class Type {
 public:
   Type(Identifier &&identifier, Modifier modifier = nodes::Modifier::CONST,
diff --git a/src/basic_type_check.cpp b/src/basic_type_check.cpp
index 84687c9..8ef990a 100644
--- a/src/basic_type_check.cpp
+++ b/src/basic_type_check.cpp
@@ -2,63 +2,62 @@
 
 namespace type_check {
 
-nodes::TypeCheckResult type_check_literal(const nodes::Literal &literal,
-                                          SourcesManager &sources_manager) {
+nodes::TypeProxy get_literal_type(const nodes::Literal &literal,
+                                  SourcesManager &sources_manager) {
   switch (literal.get_any()->index()) {
   case 0: // float
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::FLOAT));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::FLOAT);
   case 1: // double
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::DOUBLE));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::DOUBLE);
   case 2: // int32_t
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::INT));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::INT);
   case 3: // int64_t
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::LONG));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::LONG);
   case 4: // size_t
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::INDEX));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::INDEX);
   case 5: // std::string
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->add_array_of(
-            sources_manager.get_type_storage()->primitive_type(
-                builtin::types::Type::CHAR)));
-  case 6: // unicode_string
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->add_array_of(
-            sources_manager.get_type_storage()->primitive_type(
-                builtin::types::Type::UNICODE)));
-  case 7: // char
-    return nodes::TypeCheckResult(
+    return sources_manager.get_type_storage()->add_array_of(
         sources_manager.get_type_storage()->primitive_type(
             builtin::types::Type::CHAR));
-  case 8: // unicode
-    return nodes::TypeCheckResult(
+  case 6: // unicode_string
+    return sources_manager.get_type_storage()->add_array_of(
         sources_manager.get_type_storage()->primitive_type(
             builtin::types::Type::UNICODE));
+  case 7: // char
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::CHAR);
+  case 8: // unicode
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::UNICODE);
   case 9: // bool
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::BOOL));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::BOOL);
   case 10: // unit
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::UNIT));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::UNIT);
   case 11: // null
-    return nodes::TypeCheckResult(
-        sources_manager.get_type_storage()->primitive_type(
-            builtin::types::Type::NULL_OPTION));
+    return sources_manager.get_type_storage()->primitive_type(
+        builtin::types::Type::NULL_OPTION);
   }
 
   error_handling::handle_general_error("Unreachable");
   exit(1); // unreachable
 }
 
+nodes::TypeCheckResult type_check_literal(const nodes::Literal &literal,
+                                          SourcesManager &sources_manager,
+                                          nodes::MaybeTypeProxy expected_type) {
+  auto const type = get_literal_type(literal, sources_manager);
+  if (expected_type.has_value() && type != expected_type.value() {
+      return nodes::TypeCheckResult::construct_invalid_result();
+      // nodes::TypeCheckResult::fail_with(type, expected_type, literal); // TODO: create error ??
+  }
+  return nodes::TypeCheckResult(type);
+}
+
 } // namespace type_check
diff --git a/src/builders/expression_builders.cpp b/src/builders/expression_builders.cpp
index 7b37920..b1d2e8e 100644
--- a/src/builders/expression_builders.cpp
+++ b/src/builders/expression_builders.cpp
@@ -543,7 +543,7 @@ build_name_expression(parser::ParseTree::Node parser_node,
       build_node(parser_node), build_identifier(name_node),
       std::move(arguments),
       prefix_node.has_value() ? build_type(prefix_node.value(), type_storage)
-                              : std::optional<nodes::TypeProxy>(),
+                              : nodes::MaybeTypeProxy(),
       is_point_call, false);
 }
 
diff --git a/src/builders/statement_builders.cpp b/src/builders/statement_builders.cpp
index b6a5178..da98fa5 100644
--- a/src/builders/statement_builders.cpp
+++ b/src/builders/statement_builders.cpp
@@ -252,9 +252,9 @@ nodes::TypeDefinition build_type_definition(parser::ParseTree::Node parser_node,
     }
   }
 
-  std::optional<nodes::TypeProxy> type =
+  nodes::MaybeTypeProxy type =
       type_node.has_value() ? build_type(type_node.value(), type_storage)
-                            : std::optional<nodes::TypeProxy>();
+                            : nodes::MaybeTypeProxy();
 
   std::unordered_set<std::string> annotations;
 
diff --git a/src/expression_type_check.cpp b/src/expression_type_check.cpp
index 87691ce..ef76fcf 100644
--- a/src/expression_type_check.cpp
+++ b/src/expression_type_check.cpp
@@ -14,56 +14,58 @@ namespace type_check {
 
 nodes::TypeCheckResult
 type_check_expression(const nodes::Expression &expression,
-                      SourcesManager &sources_manager, State &state) {
+                      SourcesManager &sources_manager, State &state,
+                      const Arguments &arguments) {
   switch (expression.get_any()->index()) {
   // --- flow control
   case 0: // Match
     return type_check_match(*expression.get<nodes::Match>().value(),
-                            sources_manager, state);
+                            sources_manager, state, arguments);
   case 1: // Condition
     return type_check_condition(*expression.get<nodes::Condition>().value(),
-                                sources_manager, state);
+                                sources_manager, state, arguments);
   case 2: // Loop
     return type_check_loop(*expression.get<nodes::Loop>().value(),
-                           sources_manager, state);
+                           sources_manager, state, arguments);
   // --- containers
   case 3: // Container
     return type_check_container(*expression.get<nodes::Container>().value(),
-                                sources_manager, state);
+                                sources_manager, state, arguments);
   // --- modifiers
   case 4: // Return
     return type_check_return(*expression.get<nodes::Return>().value(),
-                             sources_manager, state);
+                             sources_manager, state, arguments);
   case 5: // NameDefinition
     return type_check_name_definition(
         *expression.get<nodes::NameDefinition>().value(), sources_manager,
         state);
   case 6: // Access
     return type_check_access(*expression.get<nodes::Access>().value(),
-                             sources_manager, state);
+                             sources_manager, state, arguments);
   case 7: // LoopControl
     return type_check_loop_control(
-        *expression.get<nodes::LoopControl>().value(), sources_manager, state);
+        *expression.get<nodes::LoopControl>().value(), sources_manager, state,
+        arguments);
   case 8: // ModifierExpression
     return type_check_modifier_expression(
         *expression.get<nodes::ModifierExpression>().value(), sources_manager,
-        state);
+        state, arguments);
   // --- other
   case 9: // NameExpression
     return type_check_name_expression(
         *expression.get<nodes::NameExpression>().value(), sources_manager,
-        state);
+        state, arguments);
   case 10: // Constructor
     return type_check_constructor(*expression.get<nodes::Constructor>().value(),
-                                  sources_manager, state);
+                                  sources_manager, state, arguments);
   case 11: // Lambda
     return type_check_lambda(*expression.get<nodes::Lambda>().value(),
-                             sources_manager, state);
+                             sources_manager, state, arguments);
   // --- literal
   case 12: // Literal
     // TODO
     return type_check_literal(*expression.get<nodes::Literal>().value(),
-                              sources_manager);
+                              sources_manager, arguments.expected_type);
   // --- empty lines
   case 13: // Extra
     return nodes::TypeCheckResult(
@@ -81,16 +83,21 @@ type_check_expression(const nodes::Expression &expression,
 // TODO
 nodes::TypeCheckResult type_check_match(const nodes::Match &expression,
                                         SourcesManager &sources_manager,
-                                        State &state) {} // IN PROGRESS
+                                        State &state,
+                                        const Arguments &arguments) {
+} // IN PROGRESS
 
 // TODO
 nodes::TypeCheckResult type_check_condition(const nodes::Condition &expression,
                                             SourcesManager &sources_manager,
-                                            State &state) {} // IN PROGRESS
+                                            State &state,
+                                            const Arguments &arguments) {
+} // IN PROGRESS
 
 nodes::TypeCheckResult type_check_loop(const nodes::Loop &expression,
                                        SourcesManager &sources_manager,
-                                       State &state) {
+                                       State &state,
+                                       const Arguments &arguments) {
   // TODO: ranges ??
 
   std::optional<nodes::TypeCheckResult> condition_result;
@@ -176,7 +183,8 @@ nodes::TypeCheckResult type_check_loop(const nodes::Loop &expression,
 
 nodes::TypeCheckResult type_check_array(const nodes::Container &expression,
                                         SourcesManager &sources_manager,
-                                        State &state) {
+                                        State &state,
+                                        const Arguments &arguments) {
   std::optional<nodes::TypeCheckResult> last_expression_result;
 
   for (size_t i = 0; i < expression.expressions_size(); ++i) {
@@ -214,11 +222,14 @@ nodes::TypeCheckResult type_check_array(const nodes::Container &expression,
 // TODO
 nodes::TypeCheckResult type_check_block(const nodes::Container &expression,
                                         SourcesManager &sources_manager,
-                                        State &state) {} // IN PROGRESS
+                                        State &state,
+                                        const Arguments &arguments) {
+} // IN PROGRESS
 
 nodes::TypeCheckResult type_check_container(const nodes::Container &expression,
                                             SourcesManager &sources_manager,
-                                            State &state) {
+                                            State &state,
+                                            const Arguments &arguments) {
   switch (expression.get_type()) {
   case nodes::Container::ARRAY:
     return type_check_array(expression, sources_manager, state);
@@ -233,7 +244,8 @@ nodes::TypeCheckResult type_check_container(const nodes::Container &expression,
 
 nodes::TypeCheckResult type_check_return(const nodes::Return &expression,
                                          SourcesManager &sources_manager,
-                                         State &state) {
+                                         State &state,
+                                         const Arguments &arguments) {
   auto returned_result = type_check_expression(*expression.get_expression(),
                                                sources_manager, state);
 
@@ -243,30 +255,23 @@ nodes::TypeCheckResult type_check_return(const nodes::Return &expression,
 
   switch (expression.get_type()) {
   case nodes::Return::BRING:
-    if (state.brought_type.has_value()) {
-      if (*state.brought_type.value().get() != *returned_result.get().get()) {
-        sources_manager.get_error_log()->add_error(
-            error_handling::ErrorLog::ErrorMessage(
-                expression, "Different brought type to current one",
-                error_handling::ErrorType::TYPE_CHECK));
-        return nodes::TypeCheckResult::construct_invalid_result();
-      }
-    } else {
-      state.brought_type = returned_result.get();
+    if (state.bring_type(returned_result.get())) {
+      sources_manager.get_error_log()->add_error(
+          error_handling::ErrorLog::ErrorMessage(
+              expression, "Different brought type to current one",
+              error_handling::ErrorType::TYPE_CHECK));
+      return nodes::TypeCheckResult::construct_invalid_result();
     }
     break;
   case nodes::Return::RETURN:
-    if (state.returned_type.has_value()) {
-      if (*state.returned_type.value().get() != *returned_result.get().get()) {
-        sources_manager.get_error_log()->add_error(
-            error_handling::ErrorLog::ErrorMessage(
-                expression, "Different returned type to current one",
-                error_handling::ErrorType::TYPE_CHECK));
-        return nodes::TypeCheckResult::construct_invalid_result();
-      }
-    } else {
-      state.returned_type = returned_result.get();
+    if (!state.return_type(returned_result.get())) {
+      sources_manager.get_error_log()->add_error(
+          error_handling::ErrorLog::ErrorMessage(
+              expression, "Different returned type to current one",
+              error_handling::ErrorType::TYPE_CHECK));
+      return nodes::TypeCheckResult::construct_invalid_result();
     }
+    break;
   }
 
   return nodes::TypeCheckResult(
@@ -277,12 +282,13 @@ nodes::TypeCheckResult type_check_return(const nodes::Return &expression,
 // TODO
 nodes::TypeCheckResult
 type_check_name_definition(const nodes::NameDefinition &expression,
-                           SourcesManager &sources_manager, State &state) {
-} // IN PROGRESS
+                           SourcesManager &sources_manager, State &state,
+                           const Arguments &arguments) {} // IN PROGRESS
 
 nodes::TypeCheckResult type_check_array_access(const nodes::Access &expression,
                                                SourcesManager &sources_manager,
-                                               State &state) {
+                                               State &state,
+                                               const Arguments &arguments) {
 
   auto index_result =
       type_check_expression(*expression.get_index(), sources_manager, state);
@@ -322,7 +328,8 @@ nodes::TypeCheckResult type_check_array_access(const nodes::Access &expression,
 
 nodes::TypeCheckResult type_check_tuple_access(const nodes::Access &expression,
                                                SourcesManager &sources_manager,
-                                               State &state) {
+                                               State &state,
+                                               const Arguments &arguments) {
   auto value_result =
       type_check_expression(*expression.get_value(), sources_manager, state);
 
@@ -352,7 +359,8 @@ nodes::TypeCheckResult type_check_tuple_access(const nodes::Access &expression,
 
 nodes::TypeCheckResult type_check_access(const nodes::Access &expression,
                                          SourcesManager &sources_manager,
-                                         State &state) {
+                                         State &state,
+                                         const Arguments &arguments) {
   switch (expression.get_type()) {
   case nodes::Access::ARRAY:
     return type_check_array_access(expression, sources_manager, state);
@@ -363,7 +371,8 @@ nodes::TypeCheckResult type_check_access(const nodes::Access &expression,
 
 nodes::TypeCheckResult type_check_loop_control(const nodes::LoopControl &,
                                                SourcesManager &sources_manager,
-                                               State &) {
+                                               State &,
+                                               const Arguments &arguments) {
   return nodes::TypeCheckResult(
       sources_manager.get_type_storage()->primitive_type(
           builtin::types::Type::UNIT));
@@ -371,7 +380,8 @@ nodes::TypeCheckResult type_check_loop_control(const nodes::LoopControl &,
 
 nodes::TypeCheckResult
 type_check_modifier_expression(const nodes::ModifierExpression &expression,
-                               SourcesManager &sources_manager, State &state) {
+                               SourcesManager &sources_manager, State &state,
+                               const Arguments &arguments) {
   auto modified_result = type_check_expression(*expression.get_expression(),
                                                sources_manager, state);
 
@@ -409,18 +419,20 @@ type_check_modifier_expression(const nodes::ModifierExpression &expression,
 // TODO
 nodes::TypeCheckResult
 type_check_name_expression(const nodes::NameExpression &expression,
-                           SourcesManager &sources_manager, State &state) {
-} // IN PROGRESS
+                           SourcesManager &sources_manager, State &state,
+                           const Arguments &arguments) {} // IN PROGRESS
 
 // TODO
 nodes::TypeCheckResult
 type_check_constructor(const nodes::Constructor &expression,
-                       SourcesManager &sources_manager, State &state) {
-} // IN PROGRESS
+                       SourcesManager &sources_manager, State &state,
+                       const Arguments &arguments) {} // IN PROGRESS
 
 // TODO
 nodes::TypeCheckResult type_check_lambda(const nodes::Lambda &expression,
                                          SourcesManager &sources_manager,
-                                         State &state) {} // IN PROGRESS
+                                         State &state,
+                                         const Arguments &arguments) {
+} // IN PROGRESS
 
 } // namespace type_check
diff --git a/src/nodes/type_nodes.cpp b/src/nodes/type_nodes.cpp
index 2e5e2f6..99c503a 100644
--- a/src/nodes/type_nodes.cpp
+++ b/src/nodes/type_nodes.cpp
@@ -6,4 +6,8 @@ Type *TypeProxy::get() { return type_storage_->get_type(id_); }
 
 const Type *TypeProxy::get() const { return type_storage_->get_type(id_); }
 
+bool TypeProxy::operator==(const TypeProxy& other) const {
+    return *get() == *other.get();
+}
+
 }; // namespace nodes