+/**
+ * Initialize the AST construction.
+ */
+void init_ast(void);
+
+/**
+ * Free the AST.
+ */
+void exit_ast(void);
+
+void print_expression(const expression_t *expression);
+void print_initializer(const initializer_t *initializer);
+void print_ast(const translation_unit_t *unit);
+void print_indent(void);
+void print_declaration(const entity_t *entity);
+void print_entity(const entity_t *entity);
+void change_indent(int delta);