int compare_var_ptrs_by_name (const void *, const void *, const void *);
unsigned hash_var_ptr_by_name (const void *, const void *);
+int compare_var_ptrs_by_dict_index (const void *, const void *, const void *);
+
/* Types and widths of values associated with a variable. */
enum val_type var_get_type (const struct variable *);
int var_get_width (const struct variable *);
void var_set_obs_vals (const struct variable *, struct cat_vals *);
bool var_has_obs_vals (const struct variable *);
+/* Custom attributes. */
+struct attrset *var_get_attributes (const struct variable *);
+void var_set_attributes (struct variable *, const struct attrset *);
+bool var_has_attributes (const struct variable *);
+
/* Function types. */
typedef bool var_predicate_func (const struct variable *);