Re: Why token are numbered from 258?
Peng Yu <[email protected]>
| Newsgroups | gmane.comp.parsers.bison.general |
|---|---|
| Message-ID | <CABrM6wk_w3Nhfsc430+y6X1Pvp5uSn_23J6s6_q=9q+FVN+=_A@mail.gmail.com> |
> 256 is the error token, and 257 is the undef token (when we receive unknown tokens from yylex). > > 256 is mandated by POSIX : > > https://pubs.opengroup.org/onlinepubs/007904875/utilities/yacc.html > > > The token error shall be reserved for error handling. The name error can be used in grammar rules. It indicates places where the parser can recover from a syntax error. The default value of error shall be 256. Its value can be changed using a %token declaration. The lexical analyzer should not return the value of error. > > It seems to say that we should be able to change the value with `%token error 2400`, but we don't support that. (checking...) OMG, we do support it! New test case... OK. I find 256. But 257 is not found anywhere in y.tab.c or y.tab.h? y.tab.c:#define YYERRCODE 256 Also, YYERRCODE is not found in the manual, should it be mentioned there? -- Regards, Peng _______________________________________________ [email protected] https://lists.gnu.org/mailman/listinfo/help-bison