UNION
%token <ds_val> STRUCT UNION
| UNION
{ "union", UNION, TS_UNION },
| UNION { funny(UNION); }
%term SUM INT PROD UNION INTER
case UNION:
"union", UNION,
return (UNION);
case UNION:
multiselect_op(A) ::= UNION. {A = TK_UNION;}
multiselect_op(A) ::= UNION ALL. {A = TK_ALL;}