diff --git a/AK/NonnullRefPtr.h b/AK/NonnullRefPtr.h
index 192149373cd..094d8bba440 100644
--- a/AK/NonnullRefPtr.h
+++ b/AK/NonnullRefPtr.h
@@ -58,7 +58,7 @@ public:
         const_cast<T&>(object).ref();
     }
     template<typename U>
-    ALWAYS_INLINE NonnullRefPtr(const U& object)
+    ALWAYS_INLINE NonnullRefPtr(const U& object) requires(IsConvertible<U*, T*>)
         : m_bits((FlatPtr) static_cast<const T*>(&object))
     {
         VERIFY(!(m_bits & 1));
@@ -75,7 +75,7 @@ public:
         VERIFY(!(m_bits & 1));
     }
     template<typename U>
-    ALWAYS_INLINE NonnullRefPtr(NonnullRefPtr<U>&& other)
+    ALWAYS_INLINE NonnullRefPtr(NonnullRefPtr<U>&& other) requires(IsConvertible<U*, T*>)
         : m_bits((FlatPtr)&other.leak_ref())
     {
         VERIFY(!(m_bits & 1));
@@ -86,7 +86,7 @@ public:
         VERIFY(!(m_bits & 1));
     }
     template<typename U>
-    ALWAYS_INLINE NonnullRefPtr(const NonnullRefPtr<U>& other)
+    ALWAYS_INLINE NonnullRefPtr(const NonnullRefPtr<U>& other) requires(IsConvertible<U*, T*>)
         : m_bits((FlatPtr)other.add_ref())
     {
         VERIFY(!(m_bits & 1));
@@ -119,7 +119,7 @@ public:
     }
 
     template<typename U>
-    NonnullRefPtr& operator=(const NonnullRefPtr<U>& other)
+    NonnullRefPtr& operator=(const NonnullRefPtr<U>& other) requires(IsConvertible<U*, T*>)
     {
         assign(other.add_ref());
         return *this;
@@ -133,7 +133,7 @@ public:
     }
 
     template<typename U>
-    NonnullRefPtr& operator=(NonnullRefPtr<U>&& other)
+    NonnullRefPtr& operator=(NonnullRefPtr<U>&& other) requires(IsConvertible<U*, T*>)
     {
         assign(&other.leak_ref());
         return *this;
@@ -213,7 +213,7 @@ public:
     }
 
     template<typename U>
-    void swap(NonnullRefPtr<U>& other)
+    void swap(NonnullRefPtr<U>& other) requires(IsConvertible<U*, T*>)
     {
         // NOTE: swap is not atomic!
         U* other_ptr = other.exchange(nullptr);
@@ -327,7 +327,7 @@ struct Formatter<NonnullRefPtr<T>> : Formatter<const T*> {
 };
 
 template<typename T, typename U>
-inline void swap(NonnullRefPtr<T>& a, NonnullRefPtr<U>& b)
+inline void swap(NonnullRefPtr<T>& a, NonnullRefPtr<U>& b) requires(IsConvertible<U*, T*>)
 {
     a.swap(b);
 }
diff --git a/AK/RefPtr.h b/AK/RefPtr.h
index 5031b82fe4e..e054cc99371 100644
--- a/AK/RefPtr.h
+++ b/AK/RefPtr.h
@@ -154,18 +154,18 @@ public:
     {
     }
     template<typename U>
-    ALWAYS_INLINE RefPtr(const NonnullRefPtr<U>& other)
+    ALWAYS_INLINE RefPtr(const NonnullRefPtr<U>& other) requires(IsConvertible<U*, T*>)
         : m_bits(PtrTraits::as_bits(const_cast<U*>(other.add_ref())))
     {
     }
     template<typename U>
-    ALWAYS_INLINE RefPtr(NonnullRefPtr<U>&& other)
+    ALWAYS_INLINE RefPtr(NonnullRefPtr<U>&& other) requires(IsConvertible<U*, T*>)
         : m_bits(PtrTraits::as_bits(&other.leak_ref()))
     {
         VERIFY(!is_null());
     }
     template<typename U, typename P = RefPtrTraits<U>>
-    RefPtr(RefPtr<U, P>&& other)
+    RefPtr(RefPtr<U, P>&& other) requires(IsConvertible<U*, T*>)
         : m_bits(PtrTraits::template convert_from<U, P>(other.leak_ref_raw()))
     {
     }
@@ -174,7 +174,7 @@ public:
     {
     }
     template<typename U, typename P = RefPtrTraits<U>>
-    RefPtr(const RefPtr<U, P>& other)
+    RefPtr(const RefPtr<U, P>& other) requires(IsConvertible<U*, T*>)
         : m_bits(other.add_ref_raw())
     {
     }
@@ -203,7 +203,7 @@ public:
     }
 
     template<typename U, typename P = RefPtrTraits<U>>
-    void swap(RefPtr<U, P>& other)
+    void swap(RefPtr<U, P>& other) requires(IsConvertible<U*, T*>)
     {
         // NOTE: swap is not atomic!
         FlatPtr other_bits = P::exchange(other.m_bits, P::default_null_value);
@@ -219,14 +219,14 @@ public:
     }
 
     template<typename U, typename P = RefPtrTraits<U>>
-    ALWAYS_INLINE RefPtr& operator=(RefPtr<U, P>&& other)
+    ALWAYS_INLINE RefPtr& operator=(RefPtr<U, P>&& other) requires(IsConvertible<U*, T*>)
     {
         assign_raw(PtrTraits::template convert_from<U, P>(other.leak_ref_raw()));
         return *this;
     }
 
     template<typename U>
-    ALWAYS_INLINE RefPtr& operator=(NonnullRefPtr<U>&& other)
+    ALWAYS_INLINE RefPtr& operator=(NonnullRefPtr<U>&& other) requires(IsConvertible<U*, T*>)
     {
         assign_raw(PtrTraits::as_bits(&other.leak_ref()));
         return *this;
@@ -239,7 +239,7 @@ public:
     }
 
     template<typename U>
-    ALWAYS_INLINE RefPtr& operator=(const NonnullRefPtr<U>& other)
+    ALWAYS_INLINE RefPtr& operator=(const NonnullRefPtr<U>& other) requires(IsConvertible<U*, T*>)
     {
         assign_raw(PtrTraits::as_bits(other.add_ref()));
         return *this;
@@ -253,7 +253,7 @@ public:
     }
 
     template<typename U>
-    ALWAYS_INLINE RefPtr& operator=(const RefPtr<U>& other)
+    ALWAYS_INLINE RefPtr& operator=(const RefPtr<U>& other) requires(IsConvertible<U*, T*>)
     {
         assign_raw(other.add_ref_raw());
         return *this;
@@ -470,7 +470,7 @@ inline RefPtr<T> static_ptr_cast(const RefPtr<U>& ptr)
 }
 
 template<typename T, typename PtrTraitsT, typename U, typename PtrTraitsU>
-inline void swap(RefPtr<T, PtrTraitsT>& a, RefPtr<U, PtrTraitsU>& b)
+inline void swap(RefPtr<T, PtrTraitsT>& a, RefPtr<U, PtrTraitsU>& b) requires(IsConvertible<U*, T*>)
 {
     a.swap(b);
 }
diff --git a/Kernel/FileSystem/ProcFS.cpp b/Kernel/FileSystem/ProcFS.cpp
index fb5e51d068b..176bfb04f9f 100644
--- a/Kernel/FileSystem/ProcFS.cpp
+++ b/Kernel/FileSystem/ProcFS.cpp
@@ -55,7 +55,7 @@ KResult ProcFS::initialize()
     auto root_inode = ProcFSComponentRegistry::the().root_directory().to_inode(*this);
     if (root_inode.is_error())
         return root_inode.error();
-    m_root_inode = static_cast<NonnullRefPtr<ProcFSDirectoryInode>>(root_inode.release_value());
+    m_root_inode = static_ptr_cast<ProcFSDirectoryInode>(root_inode.release_value());
 
     return KSuccess;
 }
diff --git a/Kernel/FileSystem/SysFSComponent.cpp b/Kernel/FileSystem/SysFSComponent.cpp
index 78780221111..1b3697e4992 100644
--- a/Kernel/FileSystem/SysFSComponent.cpp
+++ b/Kernel/FileSystem/SysFSComponent.cpp
@@ -61,12 +61,12 @@ SysFSDirectory::SysFSDirectory(StringView name, SysFSDirectory const& parent_dir
 {
 }
 
-NonnullRefPtr<Inode> SysFSDirectory::to_inode(SysFS const& sysfs_instance) const
+NonnullRefPtr<SysFSInode> SysFSDirectory::to_inode(SysFS const& sysfs_instance) const
 {
     return SysFSDirectoryInode::create(sysfs_instance, *this);
 }
 
-NonnullRefPtr<Inode> SysFSComponent::to_inode(SysFS const& sysfs_instance) const
+NonnullRefPtr<SysFSInode> SysFSComponent::to_inode(SysFS const& sysfs_instance) const
 {
     return SysFSInode::create(sysfs_instance, *this);
 }
diff --git a/Kernel/FileSystem/SysFSComponent.h b/Kernel/FileSystem/SysFSComponent.h
index 3e29138a5f3..cefa342650e 100644
--- a/Kernel/FileSystem/SysFSComponent.h
+++ b/Kernel/FileSystem/SysFSComponent.h
@@ -26,7 +26,7 @@ public:
     virtual RefPtr<SysFSComponent> lookup(StringView) { VERIFY_NOT_REACHED(); };
     virtual KResultOr<size_t> write_bytes(off_t, size_t, UserOrKernelBuffer const&, FileDescription*) { return EROFS; }
 
-    virtual NonnullRefPtr<Inode> to_inode(SysFS const&) const;
+    virtual NonnullRefPtr<SysFSInode> to_inode(SysFS const&) const;
 
     InodeIndex component_index() const { return m_component_index; };
 
@@ -45,7 +45,7 @@ public:
     virtual KResult traverse_as_directory(unsigned, Function<bool(FileSystem::DirectoryEntryView const&)>) const override;
     virtual RefPtr<SysFSComponent> lookup(StringView name) override;
 
-    virtual NonnullRefPtr<Inode> to_inode(SysFS const& sysfs_instance) const override final;
+    virtual NonnullRefPtr<SysFSInode> to_inode(SysFS const& sysfs_instance) const override final;
 
 protected:
     explicit SysFSDirectory(StringView name);
diff --git a/Kernel/Graphics/GraphicsManagement.cpp b/Kernel/Graphics/GraphicsManagement.cpp
index a3607dcbccd..2455cd74bfc 100644
--- a/Kernel/Graphics/GraphicsManagement.cpp
+++ b/Kernel/Graphics/GraphicsManagement.cpp
@@ -130,7 +130,7 @@ UNMAP_AFTER_INIT bool GraphicsManagement::determine_and_initialize_graphics_devi
     // Note: If no other VGA adapter is attached as m_vga_adapter, we should attach it then.
     if (!m_vga_adapter && PCI::is_io_space_enabled(address) && adapter->type() == GraphicsDevice::Type::VGACompatible) {
         dbgln("Graphics adapter @ {} is operating in VGA mode", address);
-        m_vga_adapter = adapter;
+        m_vga_adapter = static_ptr_cast<VGACompatibleAdapter>(adapter);
     }
     return true;
 }
diff --git a/Kernel/Syscalls/purge.cpp b/Kernel/Syscalls/purge.cpp
index b13c099f8e6..72057dbafe8 100644
--- a/Kernel/Syscalls/purge.cpp
+++ b/Kernel/Syscalls/purge.cpp
@@ -27,7 +27,7 @@ KResultOr<FlatPtr> Process::sys$purge(int mode)
                 if (vmobject.is_anonymous()) {
                     // In the event that the append fails, only attempt to continue
                     // the purge if we have already appended something successfully.
-                    if (!vmobjects.try_append(vmobject) && vmobjects.is_empty()) {
+                    if (!vmobjects.try_append(static_cast<Memory::AnonymousVMObject&>(vmobject)) && vmobjects.is_empty()) {
                         result = ENOMEM;
                         return IterationDecision::Break;
                     }
diff --git a/Tests/LibSQL/TestSqlDatabase.cpp b/Tests/LibSQL/TestSqlDatabase.cpp
index 9c67267c5e1..e57b7bd8a5f 100644
--- a/Tests/LibSQL/TestSqlDatabase.cpp
+++ b/Tests/LibSQL/TestSqlDatabase.cpp
@@ -16,7 +16,7 @@
 #include <LibTest/TestCase.h>
 
 NonnullRefPtr<SQL::SchemaDef> setup_schema(SQL::Database&);
-NonnullRefPtr<SQL::SchemaDef> setup_table(SQL::Database&);
+NonnullRefPtr<SQL::TableDef> setup_table(SQL::Database&);
 void insert_into_table(SQL::Database&, int);
 void verify_table_contents(SQL::Database&, int);
 void insert_and_verify(int);
@@ -28,7 +28,7 @@ NonnullRefPtr<SQL::SchemaDef> setup_schema(SQL::Database& db)
     return schema;
 }
 
-NonnullRefPtr<SQL::SchemaDef> setup_table(SQL::Database& db)
+NonnullRefPtr<SQL::TableDef> setup_table(SQL::Database& db)
 {
     auto schema = setup_schema(db);
     auto table = SQL::TableDef::construct(schema, "TestTable");
diff --git a/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp b/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
index 5d2abc435ec..fcad4a05e3c 100644
--- a/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
+++ b/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
@@ -220,7 +220,7 @@ void SpreadsheetWidget::setup_tabs(NonnullRefPtrVector<Sheet> new_sheets)
     };
 
     m_tab_widget->on_context_menu_request = [&](auto& widget, auto& event) {
-        m_tab_context_menu_sheet_view = widget;
+        m_tab_context_menu_sheet_view = static_cast<SpreadsheetView&>(widget);
         m_tab_context_menu->popup(event.screen_position());
     };
 }
diff --git a/Userland/Libraries/LibGL/Tex/TextureUnit.cpp b/Userland/Libraries/LibGL/Tex/TextureUnit.cpp
index 8b4f4870453..b8a180c447b 100644
--- a/Userland/Libraries/LibGL/Tex/TextureUnit.cpp
+++ b/Userland/Libraries/LibGL/Tex/TextureUnit.cpp
@@ -13,7 +13,7 @@ void TextureUnit::bind_texture_to_target(GLenum texture_target, const RefPtr<Tex
 {
     switch (texture_target) {
     case GL_TEXTURE_2D:
-        m_texture_target_2d = texture;
+        m_texture_target_2d = static_ptr_cast<Texture2D>(texture);
         m_currently_bound_texture = texture;
         m_currently_bound_target = GL_TEXTURE_2D;
         break;
diff --git a/Userland/Libraries/LibIMAP/Client.cpp b/Userland/Libraries/LibIMAP/Client.cpp
index 9b63733e148..7b1bef5a8ea 100644
--- a/Userland/Libraries/LibIMAP/Client.cpp
+++ b/Userland/Libraries/LibIMAP/Client.cpp
@@ -31,7 +31,7 @@ RefPtr<Promise<Empty>> Client::connect()
     }
     if (!success)
         return {};
-    m_connect_pending = Promise<bool>::construct();
+    m_connect_pending = Promise<Empty>::construct();
     return m_connect_pending;
 }
 
diff --git a/Userland/Libraries/LibIMAP/Client.h b/Userland/Libraries/LibIMAP/Client.h
index 3fb9095dbdf..cea34fe37cb 100644
--- a/Userland/Libraries/LibIMAP/Client.h
+++ b/Userland/Libraries/LibIMAP/Client.h
@@ -69,7 +69,7 @@ private:
     // Not yet sent
     Vector<Command> m_command_queue {};
 
-    RefPtr<Promise<bool>> m_connect_pending {};
+    RefPtr<Promise<Empty>> m_connect_pending {};
 
     ByteBuffer m_buffer;
     Parser m_parser;
diff --git a/Userland/Libraries/LibJS/Parser.cpp b/Userland/Libraries/LibJS/Parser.cpp
index c2cf37f9dc9..7a3437915f9 100644
--- a/Userland/Libraries/LibJS/Parser.cpp
+++ b/Userland/Libraries/LibJS/Parser.cpp
@@ -1606,7 +1606,7 @@ NonnullRefPtr<Identifier> Parser::parse_identifier()
         token.value());
 }
 
-NonnullRefPtr<CallExpression> Parser::parse_call_expression(NonnullRefPtr<Expression> lhs)
+NonnullRefPtr<Expression> Parser::parse_call_expression(NonnullRefPtr<Expression> lhs)
 {
     auto rule_start = push_start();
     if (!m_state.allow_super_constructor_call && is<SuperExpression>(*lhs))
diff --git a/Userland/Libraries/LibJS/Parser.h b/Userland/Libraries/LibJS/Parser.h
index 41b6cef2c86..b594b640408 100644
--- a/Userland/Libraries/LibJS/Parser.h
+++ b/Userland/Libraries/LibJS/Parser.h
@@ -85,7 +85,7 @@ public:
     NonnullRefPtr<StringLiteral> parse_string_literal(const Token& token, bool in_template_literal = false);
     NonnullRefPtr<TemplateLiteral> parse_template_literal(bool is_tagged);
     NonnullRefPtr<Expression> parse_secondary_expression(NonnullRefPtr<Expression>, int min_precedence, Associativity associate = Associativity::Right);
-    NonnullRefPtr<CallExpression> parse_call_expression(NonnullRefPtr<Expression>);
+    NonnullRefPtr<Expression> parse_call_expression(NonnullRefPtr<Expression>);
     NonnullRefPtr<NewExpression> parse_new_expression();
     NonnullRefPtr<ClassDeclaration> parse_class_declaration();
     NonnullRefPtr<ClassExpression> parse_class_expression(bool expect_class_name);
diff --git a/Userland/Libraries/LibPDF/Document.cpp b/Userland/Libraries/LibPDF/Document.cpp
index 473b5f5a207..582a1c90f9b 100644
--- a/Userland/Libraries/LibPDF/Document.cpp
+++ b/Userland/Libraries/LibPDF/Document.cpp
@@ -146,7 +146,7 @@ Value Document::resolve(Value const& value)
     auto obj = value.as_object();
 
     if (obj->is_indirect_value())
-        return static_cast<NonnullRefPtr<IndirectValue>>(obj)->value();
+        return static_ptr_cast<IndirectValue>(obj)->value();
 
     return obj;
 }
diff --git a/Userland/Libraries/LibPDF/Object.h b/Userland/Libraries/LibPDF/Object.h
index 47d0794de67..d7673e8ca5b 100644
--- a/Userland/Libraries/LibPDF/Object.h
+++ b/Userland/Libraries/LibPDF/Object.h
@@ -248,7 +248,7 @@ template<IsObject To, IsObject From>
 #    undef ENUMERATE_TYPES
 #endif
 
-    return static_cast<NonnullRefPtr<To>>(obj);
+    return static_ptr_cast<To>(obj);
 }
 
 }
diff --git a/Userland/Libraries/LibSQL/AST/Parser.cpp b/Userland/Libraries/LibSQL/AST/Parser.cpp
index 6230a0f91c4..d7c728a9ff0 100644
--- a/Userland/Libraries/LibSQL/AST/Parser.cpp
+++ b/Userland/Libraries/LibSQL/AST/Parser.cpp
@@ -210,7 +210,7 @@ NonnullRefPtr<Insert> Parser::parse_insert_statement(RefPtr<CommonTableExpressio
                 if ((column_names.size() > 0) && (chained_expr->expressions().size() != column_names.size())) {
                     syntax_error("Number of expressions does not match number of columns");
                 } else {
-                    chained_expressions.append(chained_expression.release_nonnull());
+                    chained_expressions.append(static_ptr_cast<ChainedExpression>(chained_expression.release_nonnull()));
                 }
             } else {
                 expected("Chained expression");
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
index 93bc19b5bf8..f84057cbec7 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLTableElement.cpp
@@ -72,7 +72,7 @@ NonnullRefPtr<HTMLTableCaptionElement> HTMLTableElement::create_caption()
 
     auto caption = DOM::create_element(document(), TagNames::caption, Namespace::HTML);
     pre_insert(caption, first_child());
-    return caption;
+    return static_ptr_cast<HTMLTableCaptionElement>(caption);
 }
 
 void HTMLTableElement::delete_caption()
@@ -159,7 +159,7 @@ NonnullRefPtr<HTMLTableSectionElement> HTMLTableElement::create_t_head()
 
     pre_insert(thead, child_to_append_after);
 
-    return thead;
+    return static_ptr_cast<HTMLTableSectionElement>(thead);
 }
 
 void HTMLTableElement::delete_t_head()
@@ -209,7 +209,7 @@ NonnullRefPtr<HTMLTableSectionElement> HTMLTableElement::create_t_foot()
 
     auto tfoot = DOM::create_element(document(), TagNames::tfoot, Namespace::HTML);
     append_child(tfoot);
-    return tfoot;
+    return static_ptr_cast<HTMLTableSectionElement>(tfoot);
 }
 
 void HTMLTableElement::delete_t_foot()
@@ -248,7 +248,7 @@ NonnullRefPtr<HTMLTableSectionElement> HTMLTableElement::create_t_body()
 
     pre_insert(tbody, child_to_append_after);
 
-    return tbody;
+    return static_ptr_cast<HTMLTableSectionElement>(tbody);
 }
 
 NonnullRefPtr<DOM::HTMLCollection> HTMLTableElement::rows()
@@ -287,7 +287,7 @@ DOM::ExceptionOr<NonnullRefPtr<HTMLTableRowElement>> HTMLTableElement::insert_ro
     if (index < -1 || index >= (long)rows_length) {
         return DOM::IndexSizeError::create("Index is negative or greater than the number of rows");
     }
-    auto tr = static_cast<NonnullRefPtr<HTMLTableRowElement>>(DOM::create_element(document(), TagNames::tr, Namespace::HTML));
+    auto tr = static_ptr_cast<HTMLTableRowElement>(DOM::create_element(document(), TagNames::tr, Namespace::HTML));
     if (rows_length == 0 && !has_child_of_type<HTMLTableRowElement>()) {
         auto tbody = DOM::create_element(document(), TagNames::tbody, Namespace::HTML);
         tbody->append_child(tr);
diff --git a/Userland/Libraries/LibWeb/Layout/TreeBuilder.cpp b/Userland/Libraries/LibWeb/Layout/TreeBuilder.cpp
index 74b52e9b41f..955416f9a93 100644
--- a/Userland/Libraries/LibWeb/Layout/TreeBuilder.cpp
+++ b/Userland/Libraries/LibWeb/Layout/TreeBuilder.cpp
@@ -166,7 +166,7 @@ void TreeBuilder::remove_irrelevant_boxes(NodeWithStyle& root)
 {
     // The following boxes are discarded as if they were display:none:
 
-    NonnullRefPtrVector<Box> to_remove;
+    NonnullRefPtrVector<Node> to_remove;
 
     // Children of a table-column.
     for_each_in_tree_with_display<CSS::Display::TableColumn>(root, [&](Box& table_column) {
diff --git a/Userland/Shell/Parser.cpp b/Userland/Shell/Parser.cpp
index 68ff39accf4..260fffbcdd2 100644
--- a/Userland/Shell/Parser.cpp
+++ b/Userland/Shell/Parser.cpp
@@ -1431,7 +1431,7 @@ RefPtr<AST::Node> Parser::parse_variable_ref()
     return create<AST::SimpleVariable>(move(name)); // Variable Simple
 }
 
-RefPtr<AST::Node> Parser::parse_slice()
+RefPtr<AST::Slice> Parser::parse_slice()
 {
     auto rule_start = push_start();
     if (!next_is("["))
diff --git a/Userland/Shell/Parser.h b/Userland/Shell/Parser.h
index 2c11d23a92c..37aac4097f9 100644
--- a/Userland/Shell/Parser.h
+++ b/Userland/Shell/Parser.h
@@ -85,7 +85,7 @@ private:
     RefPtr<AST::Node> parse_string_inner(StringEndCondition);
     RefPtr<AST::Node> parse_variable();
     RefPtr<AST::Node> parse_variable_ref();
-    RefPtr<AST::Node> parse_slice();
+    RefPtr<AST::Slice> parse_slice();
     RefPtr<AST::Node> parse_evaluate();
     RefPtr<AST::Node> parse_history_designator();
     RefPtr<AST::Node> parse_comment();