+/// lst_expr: '{' expression { ',' expression } '}'
+ex parser::parse_lst_expr()
+{
+ get_next_tok(); // eat {.
+
+ lst list;
+ if (token != '}') {
+ while (true) {
+ ex e = parse_expression(); // expression();
+ list.append(e);
+
+ if (token == '}') {
+ break;
+ }
+
+ if (token != ',') {
+ Parse_error("expected '}'");
+ }
+
+ get_next_tok(); // eat ','.
+ }
+ }
+ // Eat the '}'.
+ get_next_tok();
+
+ return list;
+}
+