diff --git a/dust-lang/src/abstract_tree/assignment.rs b/dust-lang/src/abstract_tree/assignment.rs
index b4e1bf0..92ac574 100644
--- a/dust-lang/src/abstract_tree/assignment.rs
+++ b/dust-lang/src/abstract_tree/assignment.rs
@@ -84,6 +84,18 @@ impl Evaluate for Assignment {
                     position: function_call.position,
                 });
             }
+        } else if let Some(constructor) = &self.constructor {
+            let r#type = constructor.clone().construct(&context)?;
+
+            r#type
+                .check(&statement_type)
+                .map_err(|conflict| ValidationError::TypeCheck {
+                    conflict,
+                    actual_position: self.statement.position(),
+                    expected_position: Some(constructor.position()),
+                })?;
+
+            context.set_type(self.identifier.node.clone(), r#type.clone())?;
         } else {
             context.set_type(self.identifier.node.clone(), statement_type)?;
         }
diff --git a/dust-lang/src/abstract_tree/mod.rs b/dust-lang/src/abstract_tree/mod.rs
index 91a1ce8..084fc3c 100644
--- a/dust-lang/src/abstract_tree/mod.rs
+++ b/dust-lang/src/abstract_tree/mod.rs
@@ -14,7 +14,7 @@ pub mod math;
 pub mod statement;
 pub mod structure_definition;
 pub mod r#type;
-pub mod type_alias;
+pub mod type_assignment;
 pub mod type_constructor;
 pub mod value_node;
 pub mod r#while;
@@ -42,7 +42,7 @@ pub use self::{
     r#while::While,
     statement::Statement,
     structure_definition::StructureDefinition,
-    type_alias::TypeAssignment,
+    type_assignment::TypeAssignment,
     type_constructor::{
         EnumTypeConstructor, FunctionTypeConstructor, ListTypeConstructor, TypeConstructor,
     },
diff --git a/dust-lang/src/abstract_tree/type_alias.rs b/dust-lang/src/abstract_tree/type_assignment.rs
similarity index 80%
rename from dust-lang/src/abstract_tree/type_alias.rs
rename to dust-lang/src/abstract_tree/type_assignment.rs
index 326aef5..4ed0ddb 100644
--- a/dust-lang/src/abstract_tree/type_alias.rs
+++ b/dust-lang/src/abstract_tree/type_assignment.rs
@@ -24,11 +24,11 @@ impl TypeAssignment {
 }
 
 impl Evaluate for TypeAssignment {
-    fn validate(
-        &self,
-        _context: &mut Context,
-        _manage_memory: bool,
-    ) -> Result<(), ValidationError> {
+    fn validate(&self, context: &mut Context, _manage_memory: bool) -> Result<(), ValidationError> {
+        let r#type = self.constructor.clone().construct(&context)?;
+
+        context.set_type(self.identifier.node.clone(), r#type)?;
+
         Ok(())
     }