+symbol_t *symbol_get (const char *key, location_t location);
+
+/* Generate a dummy nonterminal, whose name cannot conflict with the
+ user's names. */
+symbol_t *dummy_symbol_get (location_t location);
+
+/* Declare the new SYMBOL. Make it an alias of SYMVAL. */
+void symbol_make_alias (symbol_t *symbol, symbol_t *symval,
+ location_t location);
+
+/* Set the TYPE_NAME associated to SYMBOL. Does nothing if passed 0 as
+ TYPE_NAME. */
+void symbol_type_set (symbol_t *symbol,
+ char *type_name, location_t location);
+
+/* Set the DESTRUCTOR associated to SYMBOL. */
+void symbol_destructor_set (symbol_t *symbol,
+ char *destructor, location_t location);
+
+/* Set the PRINTER associated to SYMBOL. */
+void symbol_printer_set (symbol_t *symbol,
+ char *printer, location_t location);
+
+/* Set the PRECEDENCE associated to SYMBOL. Ensures that SYMBOL is a
+ terminal. Does nothing if invoked with UNDEF_ASSOC as ASSOC. */
+void symbol_precedence_set (symbol_t *symbol,
+ int prec, assoc_t assoc, location_t location);
+
+/* Set the CLASS associated to SYMBOL. */
+void symbol_class_set (symbol_t *symbol,
+ symbol_class class, location_t location);
+
+/* Set the USER_TOKEN_NUMBER associated to SYMBOL. */
+void symbol_user_token_number_set (symbol_t *symbol,
+ int user_number, location_t location);