| rhses.1 ";"
;
+%token PERCENT_EMPTY "%empty";
rhs:
/* Nothing. */
{ grammar_current_rule_begin (current_lhs_symbol, current_lhs_location,
{ grammar_current_rule_action_append ($2, @2, $3, false); }
| rhs "%?{...}"
{ grammar_current_rule_action_append ($2, @2, NULL, true); }
+| rhs "%empty"
+ { grammar_current_rule_empty_set (@2); }
| rhs "%prec" symbol
{ grammar_current_rule_prec_set ($3, @3); }
| rhs "%dprec" INT