+};
+
+/* Undefined user number. */
+#define USER_NUMBER_UNDEFINED -1
+
+/* `symbol->user_token_number == USER_NUMBER_ALIAS' means this symbol
+ *has* (not is) a string literal alias. For instance, `%token foo
+ "foo"' has `"foo"' numbered regularly, and `foo' numbered as
+ USER_NUMBER_ALIAS. */
+#define USER_NUMBER_ALIAS -9991
+
+/* Undefined internal token number. */
+#define NUMBER_UNDEFINED ((token_number_t) -1)