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diff --git a/tiger-compiler/src/ast/non-object-visitor.hh b/tiger-compiler/src/ast/non-object-visitor.hh
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+++ b/tiger-compiler/src/ast/non-object-visitor.hh
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+/**
+ ** \file ast/non-object-visitor.hh
+ ** \brief Provide aborting visits for object-related nodes.
+ */
+
+#pragma once
+
+#include <ast/visitor.hh>
+
+namespace ast
+{
+  /** GenNonObjectVisitor<CONSTNESS-SELECTOR> provides aborting visit
+      methods for object-related nodes.  This class is meant to factor
+      the code visiting object-related nodes in visitors bound to
+      process AST \em without objects.
+
+      ast::GenNonObjectVisitor inherits virtually from ast::GenVisitor
+      to allow diamond inheritance, notably for a ``compatibility''
+      purpose with ast::GenDefaultVisitor.
+
+      For instance, type::TypeChecker, a visitor that checks the types
+      of an AST without objects, inherits from ast::DefaultVisitor to
+      factor default (``empty'') traversal implementations, and from
+      ast::NonObjectVisitor to get an aborting behavior for
+      object-related nodes.
+
+      \verbatim
+
+                             /ast::Visitor/
+                                   ^
+                (virtual)          |          (virtual)
+                    ,--------------+--------------.
+                    |                             |
+                    |                             |
+          /ast::DefaultVisitor/         /ast::NonObjectVisitor/
+                    ^                             ^
+                    |                             |
+                    `--------------+--------------'
+                                   |
+                                   |
+                           type::TypeChecker
+
+      \endverbatim
+  */
+  template <template <typename> class Const>
+  class GenNonObjectVisitor : virtual public GenVisitor<Const>
+  {
+  public:
+    /// Super class type.
+    using super_type = GenVisitor<Const>;
+
+    // Import overloaded virtual functions.
+    using super_type::operator();
+
+    /// Convenient abbreviation.
+    template <typename Type> using const_t = typename Const<Type>::type;
+
+    /** \name Ctor & dtor.
+     ** \{ */
+    /// Construct a non-object visitor.
+    GenNonObjectVisitor();
+    /// Destroy a non-object visitor.
+    virtual ~GenNonObjectVisitor();
+    /** \} */
+
+    /// \name Object-related visits.
+    ///
+    /// The methods should not be used, since this visitor is for the
+    /// non-object flavor of the language.
+    /// \{
+    void operator()(const_t<ClassTy>& e) override;
+
+    void operator()(const_t<MethodChunk>& e) override;
+    void operator()(const_t<MethodDec>& e) override;
+
+    void operator()(const_t<MethodCallExp>& e) override;
+    void operator()(const_t<ObjectExp>& e) override;
+    /// \}
+  };
+
+  /// Shorthand for a const visitor.
+  using NonObjectConstVisitor = GenNonObjectVisitor<misc::constify_traits>;
+  /// Shorthand for a non const visitor.
+  using NonObjectVisitor = GenNonObjectVisitor<misc::id_traits>;
+
+#ifdef SWIG
+  %template(NonObjectConstVisitor) GenNonObjectVisitor<misc::constify_traits>;
+  %template(NonObjectVisitor) GenNonObjectVisitor<misc::id_traits>;
+#endif
+} // namespace ast
+
+#include <ast/non-object-visitor.hxx>