How to set friendly name for "$end"?
Szabolcs Horvát <[email protected]> Fri, 6 May 2022 11:12:49 +0200
| Newsgroups | gmane.comp.parsers.bison.general |
|---|---|
| Message-ID | <CAJDnrnqFbW3UYcSYJx9ax5nYjLqrWtJaJzpRqLYnu5rQ5yzmZA@mail.gmail.com> |
Hello, Error messages issued by Bison-generated parsers sometimes mention the special token "$end", which is confusing to end users. Normal tokens can be given a friendly names using %token MYTOKEN "my token" Is it possible to set a friendly name for $end as well? Recent versions of Bison format $end as "end of file". I am looking for a solution that works in older versions as well. Version 3.5 is a must, versions 3.0 and 2.3 (which ships with macOS) are highly preferable. One solution that has been proposed to me (see https://stackoverflow.com/q/72130611/695132) is to use %token END 0 "end of file" This does indeed work in all versions, including 2.3. But it is unclear to me if it is safe. Is it guaranteed that $end corresponds to 0? Thanks for any hints in advance, Szabolcs