Re: Why token are numbered from 258?
Pavel Stehule <[email protected]>
| Newsgroups | gmane.comp.parsers.bison.general |
|---|---|
| Message-ID | <CAFj8pRA9sF3CgDDqEt4nVWX6GuT2hX-++m3FzqkAHQ_BVCE=9g@mail.gmail.com> |
čt 7. 2. 2019 v 20:35 odesílatel Christian Schoenebeck < [email protected]> napsal: > On Donnerstag, 7. Februar 2019 11:33:38 CET Peng Yu wrote: > > I don't quite understand why tokens are numbered starting from 258. > > What are 256 and 257 for? Thanks. > > the one byte encodings like ASCII can has 256 chars. The gramatic can be mix of special chars like ();, ... and words (tokens). You don't need to declare special tokens for one char symbols. Regards Pavel > It's been a while, but as far as I can remember those extra 2 are always > automatically used for the special built-in terminals YYEOF and YYEMPTY. > > Best regards, > Christian Schoenebeck > > _______________________________________________ > [email protected] https://lists.gnu.org/mailman/listinfo/help-bison > _______________________________________________ [email protected] https://lists.gnu.org/mailman/listinfo/help-bison