- if (!parse_variables_const (lexer, dataset_dict (ds), &v_variables, &n_variables,
- PV_APPEND | PV_NO_SCRATCH))
+ /* Get list of current variables, to avoid duplicates. */
+ vars = xmalloc (frq->n_vars * sizeof *vars);
+ n_vars = frq->n_vars;
+ for (i = 0; i < frq->n_vars; i++)
+ vars[i] = frq->vars[i].var;
+
+ if (!parse_variables (lexer, dataset_dict (ds), &vars, &n_vars,
+ PV_APPEND | PV_NO_SCRATCH))