-int val_labs_add (struct val_labs *, union value, const char *);
-int val_labs_replace (struct val_labs *, union value, const char *);
-int val_labs_remove (struct val_labs *, union value);
+bool val_labs_can_set_width (const struct val_labs *, int new_width);
+void val_labs_set_width (struct val_labs *, int new_width);
+
+bool val_labs_add (struct val_labs *, union value, const char *);
+void val_labs_replace (struct val_labs *, union value, const char *);
+bool val_labs_remove (struct val_labs *, union value);