/** Set the input string to be parsed by ginac_yyparse() (used internally). */
extern void set_lexer_string(const std::string &s);
+/** Get name of symbol/index (used internally). */
+extern std::string get_symbol_name(const ex & s);
+
/** Set the list of predefined symbols for the lexer (used internally). */
extern void set_lexer_symbols(ex l);