• Bootstrapping yacc in yacc -> Bootstrapping yacc in lex!

    From Rock Brentwood@21:1/5 to All on Sun Apr 4 13:27:53 2021
    From Kaz Kylheku:
    You could simply allow rules of this form
    ":" right side ...
    With a semantic restrction that this must be preceded by a rule that
    is not terminated with a semicolon, whose last element is a symbol:

    In other words: post-processing. That's not too much different that
    the id + colon hack.

    I misspoke in my earlier post. The hack was not created by Bison, but
    has been around and *is* part of the grammar in the POSIX standard. So
    the yacc grammar in the POSIX standard is LALR(1). I also see the hack
    done in the Sun version of UNIX hack.
    [I believe that hack goes way back. It always seemed to me ironic that
    the grammar for yacc, the most popular LALR(1) parser generator, isn't
    quite LALR(1). The original Unix yacc used the id+colon hack in C code. -John]

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)