void (*var_added) (struct dictionary *, int, void *);
void (*var_deleted) (struct dictionary *, int, void *);
void (*var_changed) (struct dictionary *, int, void *);
void (*var_added) (struct dictionary *, int, void *);
void (*var_deleted) (struct dictionary *, int, void *);
void (*var_changed) (struct dictionary *, int, void *);