diff --git a/rust/saturn/src/model/definitions.rs b/rust/saturn/src/model/definitions.rs
index f26c7ce8..b5614842 100644
--- a/rust/saturn/src/model/definitions.rs
+++ b/rust/saturn/src/model/definitions.rs
@@ -156,38 +156,7 @@ pub struct ClassDefinition {
     mixins: Vec<Mixin>,
 }
 
-/// A singleton class definition created from `class << X` syntax.
-/// This is created only when `class << X` syntax is encountered, NOT for `def self.foo`.
-/// Methods with receivers (like `def self.foo`) have their `receiver` field set instead.
-///
-/// # Examples
-/// ```ruby
-/// class Foo
-///   class << self     # attached_target = NameId("Foo")
-///     def bar; end
-///   end
-/// end
-///
-/// class << Foo        # attached_target = NameId("Foo")
-///   def baz; end
-/// end
-/// ```
-#[derive(Debug)]
-pub struct SingletonClassDefinition {
-    /// The name of this singleton class (e.g., `<Foo>` for `class << self` inside `class Foo`)
-    name_id: NameId,
-    uri_id: UriId,
-    offset: Offset,
-    comments: Vec<Comment>,
-    /// The definition where `class << X` was found (lexical owner)
-    lexical_nesting_id: Option<DefinitionId>,
-    /// Members defined directly in this singleton class
-    members: Vec<DefinitionId>,
-    /// Mixins declared in this singleton class
-    mixins: Vec<Mixin>,
-}
-
-impl SingletonClassDefinition {
+impl ClassDefinition {
     #[must_use]
     pub const fn new(
         name_id: NameId,
@@ -195,6 +164,7 @@ impl SingletonClassDefinition {
         offset: Offset,
         comments: Vec<Comment>,
         lexical_nesting_id: Option<DefinitionId>,
+        superclass_ref: Option<NameId>,
     ) -> Self {
         Self {
             name_id,
@@ -202,6 +172,7 @@ impl SingletonClassDefinition {
             offset,
             comments,
             lexical_nesting_id,
+            superclass_ref,
             members: Vec::new(),
             mixins: Vec::new(),
         }
@@ -238,25 +209,61 @@ impl SingletonClassDefinition {
     }
 
     #[must_use]
-    pub fn members(&self) -> &[DefinitionId] {
-        &self.members
+    pub fn superclass_ref(&self) -> Option<NameId> {
+        self.superclass_ref
     }
 
     #[must_use]
-    pub fn mixins(&self) -> &[Mixin] {
-        &self.mixins
+    pub fn members(&self) -> &[DefinitionId] {
+        &self.members
     }
 
     pub fn add_member(&mut self, member_id: DefinitionId) {
         self.members.push(member_id);
     }
 
+    #[must_use]
+    pub fn mixins(&self) -> &[Mixin] {
+        &self.mixins
+    }
+
     pub fn add_mixin(&mut self, mixin: Mixin) {
         self.mixins.push(mixin);
     }
 }
 
-impl ClassDefinition {
+/// A singleton class definition created from `class << X` syntax.
+/// This is created only when `class << X` syntax is encountered, NOT for `def self.foo`.
+/// Methods with receivers (like `def self.foo`) have their `receiver` field set instead.
+///
+/// # Examples
+/// ```ruby
+/// class Foo
+///   class << self     # attached_target = NameId("Foo")
+///     def bar; end
+///   end
+/// end
+///
+/// class << Foo        # attached_target = NameId("Foo")
+///   def baz; end
+/// end
+/// ```
+#[derive(Debug)]
+pub struct SingletonClassDefinition {
+    /// The name of this singleton class (e.g., `<Foo>` for `class << self` inside `class Foo`)
+    name_id: NameId,
+    uri_id: UriId,
+    offset: Offset,
+    comments: Vec<Comment>,
+    /// The definition where `class << X` was found (lexical owner)
+    lexical_nesting_id: Option<DefinitionId>,
+    /// Members defined directly in this singleton class
+    members: Vec<DefinitionId>,
+    /// Mixins declared in this singleton class
+    mixins: Vec<Mixin>,
+}
+
+impl SingletonClassDefinition {
     #[must_use]
     pub const fn new(
         name_id: NameId,
@@ -264,7 +271,6 @@ impl ClassDefinition {
         offset: Offset,
         comments: Vec<Comment>,
         lexical_nesting_id: Option<DefinitionId>,
-        superclass_ref: Option<NameId>,
     ) -> Self {
         Self {
             name_id,
@@ -272,7 +278,6 @@ impl ClassDefinition {
             offset,
             comments,
             lexical_nesting_id,
-            superclass_ref,
             members: Vec::new(),
             mixins: Vec::new(),
         }
@@ -308,25 +313,20 @@ impl ClassDefinition {
         &self.lexical_nesting_id
     }
 
-    #[must_use]
-    pub fn superclass_ref(&self) -> Option<NameId> {
-        self.superclass_ref
-    }
-
     #[must_use]
     pub fn members(&self) -> &[DefinitionId] {
         &self.members
     }
 
-    pub fn add_member(&mut self, member_id: DefinitionId) {
-        self.members.push(member_id);
-    }
-
     #[must_use]
     pub fn mixins(&self) -> &[Mixin] {
         &self.mixins
     }
 
+    pub fn add_member(&mut self, member_id: DefinitionId) {
+        self.members.push(member_id);
+    }
+
     pub fn add_mixin(&mut self, mixin: Mixin) {
         self.mixins.push(mixin);
     }